fix translation polisher safe outputs

Constrain the Translation Polisher to emit each safe output type at most once and require exact managed PR-body markers so safe output validation can complete.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: DanWahlin

.github/workflows/translation-polisher.md

@@ -129,6 +129,17 @@ Do not edit:
 15. Add the `translation-polished` label only when every changed target-language file is A- or higher.
 16. Add a short pull request comment summarizing what was polished, which languages were touched, and the final grade range.
 
+## Safe output limits
+
+Emit each safe output type at most once:
+
+- At most one `push_to_pull_request_branch`.
+- At most one `update_pull_request`.
+- At most one `add_labels`.
+- At most one `add_comment`.
+
+Do not emit duplicate label or comment requests. If a label is already present, do not emit an `add_labels` request for it. If you need to report both a quality summary and polishing summary, combine them into the single allowed pull request comment.
+
 ## Quality checklist
 
 For every translated Markdown file you edit:
@@ -207,7 +218,7 @@ Apply the profile only when that language is present in the pull request.
 
 ## Pull request body update
 
-After the final review, update the pull request body with a managed translation-quality section. Replace only the managed block between these markers:
+After the final review, update the pull request body with a managed translation-quality section. Replace only the managed block between these exact lowercase markers:
 
 ```markdown
 <!-- translation-quality-review:start -->
@@ -220,7 +231,7 @@ The body must include exactly one managed block and exactly one section inside t
 ## Translation Quality Review
 ```
 
-If an older unmarked `## Translation Quality Review` section already exists, replace it with the marked block. Do not append duplicates. Do not place generated workflow footers, integrity notes, or unrelated comments inside the managed block.
+If an older unmarked `## Translation Quality Review` section already exists, replace it with the marked block. Do not append duplicates. Do not change the marker casing. Do not place generated workflow footers, integrity notes, or unrelated comments inside the managed block.
 
 Use this format: