l10n: add .gitattributes to simplify location filtering

To simplify the location filtering process for l10n contributors when
committing po/XX.po files, add filter attributes for selected PO
files to the repository. This ensures all contributors automatically
get the same filter configuration without manual setup in
.git/info/attributes.

The default filter (gettext-no-location) is applied to all .po files
except:

- Legacy, unmaintained PO files that still contain location comments.
  Leaving the filter off avoids index vs working-tree discrepancies for
  these files. The CI pipeline will report an error when future updates
  touch these legacy files.
- Some PO files use a different filter that strips only line numbers
  from location comments while keeping filenames.

Contributors still need to manually define the filter drivers via
git-config as documented in po/README.md.

Four PO files that use location filtering (po/ca.po, po/es.po, po/ga.po,
po/ru.po) were batch-modified so their on-disk format matches the filter
output (e.g. line wrapping), avoiding index vs working-tree mismatch.

Additionally, po/README.md has been reorganized: the material on
preparing location-less PO files for commit has been moved from
"Updating a XX.po file" to a separate "Preparing a XX.po file for
commit" section. This prevents AI agents from introducing unrelated
operations when updating PO files.

Signed-off-by: Jiang Xin <worldhello.net@gmail.com>

Author: jiangxin

po/.gitattributes

@@ -0,0 +1,35 @@
+# Git Attributes for PO Files
+#
+# This file configures Git filters to automatically strip location information
+# from PO files when committing, producing cleaner diffs and saving repository
+# space.
+#
+# Two filter types are used:
+# 1. gettext-no-location: Strips both filenames and line numbers
+#    (e.g., removes "#: main.c:123" entirely)
+# 2. gettext-no-line-number: Preserves filenames but removes line numbers, which
+#    requires gettext 0.20 or higher
+#    (e.g., "#: main.c:123" becomes "#: main.c")
+#
+# See `po/README.md` for instructions on setting up the required filter drivers.
+
+# Default: Strip the whole location comments for all .po files
+*.po	filter=gettext-no-location
+
+# Legacy, unmaintained PO files: filter disabled to avoid index vs
+# working-tree mismatch (these files still have location comments).
+el.po	-filter
+is.po	-filter
+it.po	-filter
+ko.po	-filter
+pl.po	-filter
+pt_PT.po	-filter
+
+# These files use gettext-no-line-number (keep filenames, strip line
+# numbers). The choice is per l10n team preference. Requires gettext 0.20+.
+# The only benefit is locating source files from location comments when
+# the .po file is not updated from the POT via make po-update.
+ca.po	filter=gettext-no-line-number
+id.po	filter=gettext-no-line-number
+zh_CN.po	filter=gettext-no-line-number
+zh_TW.po	filter=gettext-no-line-number

po/README.md

@@ -159,38 +159,6 @@ It will:
   and these location lines will help translation tools to locate
   translation context easily.
 
-Once you are done testing the translation (see below), it's better
-to commit a location-less "po/XX.po" file to save repository space
-and make a user-friendly patch for review.
-
-To save a location-less "po/XX.po" automatically in repository, you
-can:
-
-First define a new attribute for "po/XX.po" by appending the following
-line in ".git/info/attributes":
-
-```
-/po/XX.po filter=gettext-no-location
-```
-
-Then define the driver for the "gettext-no-location" clean filter to
-strip out both filenames and locations from the contents as follows:
-
-```shell
-git config --global filter.gettext-no-location.clean \
-           "msgcat --no-location -"
-```
-
-For users who have gettext version 0.20 or higher, it is also possible
-to define a clean filter to preserve filenames but not locations:
-
-```shell
-git config --global filter.gettext-no-location.clean \
-           "msgcat --add-location=file -"
-```
-
-You're now ready to ask the l10n coordinator to pull from you.
-
 
 ## Fuzzy translation
 
@@ -229,6 +197,45 @@ git-po-helper check-commits <rev-list-opts>
 ```
 
 
+## Preparing a "XX.po" file for commit
+
+Once you are done testing the translation, it's better to commit a
+location-less "po/XX.po" file to save repository space and make a
+user-friendly patch for review.
+
+To save a location-less "po/XX.po" automatically in the repository,
+follow these steps:
+
+First, check which filter is configured for your "po/XX.po" file:
+
+```
+git check-attr filter po/XX.po
+```
+
+The filter configuration is defined in the "po/.gitattributes" file.
+
+Then define the driver for the filter. Most languages use the
+"gettext-no-location" clean filter, which strips out both filenames and line
+numbers from location comments. To set this up, run the following command:
+
+```shell
+git config --global filter.gettext-no-location.clean \
+           "msgcat --no-location -"
+```
+
+Some PO files use the "gettext-no-line-number" clean filter, which keeps
+filenames but strips line numbers. This filter requires gettext 0.20 or
+later. The only benefit is being able to locate source files from location
+comments when the .po file is not updated from the POT via `make po-update`.
+
+```shell
+git config --global filter.gettext-no-line-number.clean \
+           "msgcat --add-location=file -"
+```
+
+You're now ready to ask the l10n coordinator to pull from you.
+
+
 ## Marking strings for translation
 
 (This is done by the core developers).

po/ca.po

@@ -512,8 +512,8 @@ msgstr ""
 #, c-format
 msgid "Discard mode change from index and worktree [y,n,q,a,d%s,?]? "
 msgstr ""
-"Descarta el canvi de mode de l'índex i de l'arbre de treball [y,n,q,a,d"
-"%s,?]? "
+"Descarta el canvi de mode de l'índex i de l'arbre de treball "
+"[y,n,q,a,d%s,?]? "
 
 #: add-patch.c
 #, c-format
@@ -3879,11 +3879,11 @@ msgstr "HEAD no trobat sota refs/heads!"
 
 #: builtin/branch.c
 msgid ""
-"branch with --recurse-submodules can only be used if submodule."
-"propagateBranches is enabled"
+"branch with --recurse-submodules can only be used if "
+"submodule.propagateBranches is enabled"
 msgstr ""
-"la branca amb --recurse-submodules només es pot utilitzar si submodule."
-"propagateBranches està habilitat"
+"la branca amb --recurse-submodules només es pot utilitzar si "
+"submodule.propagateBranches està habilitat"
 
 #: builtin/branch.c
 msgid "--recurse-submodules can only be used to create branches"
@@ -7983,11 +7983,11 @@ msgstr "el protocol no admet --negotiate-only, se surt"
 
 #: builtin/fetch.c
 msgid ""
-"--filter can only be used with the remote configured in extensions."
-"partialclone"
+"--filter can only be used with the remote configured in "
+"extensions.partialclone"
 msgstr ""
-"--filter només es pot utilitzar amb el remot configurat en extensions."
-"partialclone"
+"--filter només es pot utilitzar amb el remot configurat en "
+"extensions.partialclone"
 
 #: builtin/fetch.c
 msgid "--atomic can only be used when fetching from one remote"
@@ -11436,8 +11436,8 @@ msgid ""
 "| -C) <object>] [<object>] [-e]"
 msgstr ""
 "git notes [--ref <referència-notes>] add [-f] [--allow-empty] [--"
-"[no-]separator|--separator=<salt-paràgraf>] [--[no-]stripspace] [-m <msg> | -"
-"F <fitxer> | (-c | -C) <objecte>] [<objecte>]"
+"[no-]separator|--separator=<salt-paràgraf>] [--[no-]stripspace] [-m <msg> | "
+"-F <fitxer> | (-c | -C) <objecte>] [<objecte>]"
 
 #: builtin/notes.c
 msgid "git notes [--ref <notes-ref>] copy [-f] <from-object> <to-object>"
@@ -11451,8 +11451,8 @@ msgid ""
 "| -C) <object>] [<object>] [-e]"
 msgstr ""
 "git notes [--ref <referència-notes>] append [--allow-empty] [--"
-"[no-]separator|--separator=<salt-paràgraf>] [--[no-]stripspace] [-m <msg> | -"
-"F <fitxer> | (-c | -C) <objecte>] [<objecte>] [-e]"
+"[no-]separator|--separator=<salt-paràgraf>] [--[no-]stripspace] [-m <msg> | "
+"-F <fitxer> | (-c | -C) <objecte>] [<objecte>] [-e]"
 
 #: builtin/notes.c
 msgid "git notes [--ref <notes-ref>] edit [--allow-empty] [<object>]"
@@ -13231,8 +13231,8 @@ msgstr "--empty=ask és obslolet; utilitzeu '--empty=stop' en el seu lloc."
 #: builtin/rebase.c
 #, c-format
 msgid ""
-"unrecognized empty type '%s'; valid values are \"drop\", \"keep\", and \"stop"
-"\"."
+"unrecognized empty type '%s'; valid values are \"drop\", \"keep\", and "
+"\"stop\"."
 msgstr ""
 "tipus buit «%s» no reconegut; els valors vàlids són \"drop\", \"keep\" i "
 "\"stop\"."
@@ -14440,8 +14440,8 @@ msgid ""
 msgstr ""
 "Els reempaquetaments incrementals són incompatibles amb els índexs de mapes "
 "de bits.  Useu\n"
-"--no-write-bitmap-index o inhabiliteu el paràmetre de configuració pack."
-"writeBitmaps."
+"--no-write-bitmap-index o inhabiliteu el paràmetre de configuració "
+"pack.writeBitmaps."
 
 #: builtin/repack.c
 msgid "could not start pack-objects to repack promisor objects"
@@ -19350,11 +19350,11 @@ msgstr ""
 #: commit-graph.c
 #, c-format
 msgid ""
-"attempting to write a commit-graph, but 'commitGraph."
-"changedPathsVersion' (%d) is not supported"
+"attempting to write a commit-graph, but 'commitGraph.changedPathsVersion' "
+"(%d) is not supported"
 msgstr ""
-"s'ha intentat escriure un graf de comissió, però no s'admet 'commitGraph."
-"changedPathsVersion' (%d)"
+"s'ha intentat escriure un graf de comissió, però no s'admet "
+"'commitGraph.changedPathsVersion' (%d)"
 
 #: commit-graph.c
 msgid "too many commits to write graph"
@@ -22940,8 +22940,8 @@ msgstr "el fitxer de l'índex multipaquet %s és massa petit"
 #, c-format
 msgid "multi-pack-index signature 0x%08x does not match signature 0x%08x"
 msgstr ""
-"la signatura de l'índex multipaquet 0x%08x no coincideix amb la signatura 0x"
-"%08x"
+"la signatura de l'índex multipaquet 0x%08x no coincideix amb la signatura "
+"0x%08x"
 
 #: midx.c
 #, c-format

po/es.po

@@ -391,8 +391,8 @@ msgstr ""
 #, c-format, perl-format
 msgid "Apply mode change to index and worktree [y,n,q,a,d%s,?]? "
 msgstr ""
-"¿Aplicar cambio de modo para el índice y el árbol de trabajo [y,n,q,a,"
-"d%s,?]? "
+"¿Aplicar cambio de modo para el índice y el árbol de trabajo "
+"[y,n,q,a,d%s,?]? "
 
 #, c-format, perl-format
 msgid "Apply deletion to index and worktree [y,n,q,a,d%s,?]? "
@@ -2294,9 +2294,9 @@ msgid ""
 "=<term>] [--no-checkout] [--first-parent] [<bad> [<good>...]] [--] "
 "[<paths>...]"
 msgstr ""
-"git bisect--helper --bisect-start [--term-{new,bad}=<término> --term-{old,"
-"good}=<término>] [--no-checkout] [--first-parent] [<malo> [<bueno>...]] [--] "
-"[<rutas>...]"
+"git bisect--helper --bisect-start [--term-{new,bad}=<término> --term-"
+"{old,good}=<término>] [--no-checkout] [--first-parent] [<malo> [<bueno>...]] "
+"[--] [<rutas>...]"
 
 msgid "git bisect--helper --bisect-state (bad|new) [<rev>]"
 msgstr "git bisect--helper --bisect-state (bad|new) [<rev>]"
@@ -2983,11 +2983,11 @@ msgid "HEAD not found below refs/heads!"
 msgstr "¡HEAD no encontrado dentro de refs/heads!"
 
 msgid ""
-"branch with --recurse-submodules can only be used if submodule."
-"propagateBranches is enabled"
+"branch with --recurse-submodules can only be used if "
+"submodule.propagateBranches is enabled"
 msgstr ""
-"branch con --recurse-submodules solo se puede usar si submodule."
-"propagateBranches está habilitado"
+"branch con --recurse-submodules solo se puede usar si "
+"submodule.propagateBranches está habilitado"
 
 msgid "--recurse-submodules can only be used to create branches"
 msgstr "--recurse-submodules solo se puede usar para crear ramas"
@@ -5983,11 +5983,11 @@ msgid "protocol does not support --negotiate-only, exiting"
 msgstr "el protocolo no soporta --negotiate-only, saliendo"
 
 msgid ""
-"--filter can only be used with the remote configured in extensions."
-"partialclone"
+"--filter can only be used with the remote configured in "
+"extensions.partialclone"
 msgstr ""
-"--filter solo puede ser usado con el remoto configurado en extensions."
-"partialclone"
+"--filter solo puede ser usado con el remoto configurado en "
+"extensions.partialclone"
 
 msgid "--atomic can only be used when fetching from one remote"
 msgstr "--atomic solo se puede usar cuando se busca desde un control remoto"
@@ -8914,8 +8914,8 @@ msgstr "objeto esperado en el desplazamiento %<PRIuMAX> en el paquete %s"
 
 msgid "disabling bitmap writing, packs are split due to pack.packSizeLimit"
 msgstr ""
-"deshabilitando escritura bitmap, paquetes son divididos debido a pack."
-"packSizeLimit"
+"deshabilitando escritura bitmap, paquetes son divididos debido a "
+"pack.packSizeLimit"
 
 msgid "Writing objects"
 msgstr "Escribiendo objetos"
@@ -9489,8 +9489,8 @@ msgstr ""
 msgid ""
 "\n"
 "To avoid automatically configuring upstream branches when their name\n"
-"doesn't match the local branch, see option 'simple' of branch."
-"autoSetupMerge\n"
+"doesn't match the local branch, see option 'simple' of "
+"branch.autoSetupMerge\n"
 "in 'git help config'.\n"
 msgstr ""
 "\n"