chore(copilot): add copilot instructions to prevent localization file review noise (#31585)

Author: chaosmirage

.github/instructions/localization.instructions.md

@@ -0,0 +1,39 @@
+---
+applyTo: "**/localization/messages/**/*.json"
+---
+
+# CRITICAL: DO NOT REVIEW LOCALIZATION FILES
+
+These files are managed by a dedicated localization team through a separate workflow.
+
+## Absolute Prohibitions - You MUST NOT:
+
+- ❌ NEVER suggest translating English text to other languages
+- ❌ NEVER comment that text should be translated to match the locale
+- ❌ NEVER suggest alternative translations or phrasings in any language
+- ❌ NEVER comment on language consistency (e.g., "this should be in Arabic")
+- ❌ NEVER suggest changing text content for localization purposes
+- ❌ NEVER comment on which language should be used
+- ❌ NEVER suggest adding or removing message keys
+- ❌ NEVER provide language-specific style recommendations
+
+## Why These Files Are Off-Limits:
+
+Translation suggestions make PR pages UNRESPONSIVE and overwhelm human reviewers. The localization team handles all translation work through a separate quality assurance process.
+
+## The ONLY Acceptable Comments:
+
+✅ Critical JSON syntax errors that would break the build (missing commas, unclosed brackets)
+✅ Severe grammar errors (ONLY if they would cause user confusion)
+
+## Examples of FORBIDDEN Comments:
+
+- ❌ "This English text should be translated to Arabic"
+- ❌ "Translation is missing for this locale"
+- ❌ "Consider translating '(No subject)' to '(بدون موضوع)'"
+- ❌ "This text is in English but should be in German"
+- ❌ "Inconsistent language - use native translation"
+
+If you have ANY doubt about whether to comment on a localization file, DO NOT COMMENT.
+
+Focus your review on actual code files instead.