docs: fix i18n build crash from mistranslated image directive (hr)

With gettext_additional_targets=["image"], `.. image:: <uri>` lines are
translatable msgids. The Croatian settings-editor catalog had this entry
mistranslated to leftover placeholder prose instead of the directive, so
sphinx's i18n transform re-parsed it to an image node with no uri and
crashed the whole per-locale build (KeyError: 'uri' at i18n.py:607,
"reading sources ... settings-editor") on Sphinx 9.0.4 / docutils 0.22.4.

Restore the directive verbatim. Verified by building all 26 locales under
the exact CI toolchain: 0 crashes, 0 warnings. A tree-wide audit confirms
this was the only mistranslated image/figure directive.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Author: kwagyeman

docs/locale/hr/LC_MESSAGES/openmvcam/tutorial/tools/ide/settings-editor.po

@@ -91,9 +91,7 @@ msgstr ""
 
 #: ../../openmvcam/tutorial/tools/ide/settings-editor.rst:29
 msgid ".. image:: figures/settings-editor.png"
-msgstr ""
-"PLACEHOLDER: the settings editor with a configuration open -- the controls "
-"from the JSON file laid out as a form, with the Save button at the bottom."
+msgstr ".. image:: figures/settings-editor.png"
 
 #: ../../openmvcam/tutorial/tools/ide/settings-editor.rst:33
 msgid ""