feat: add French language support

[shivangtanwar]

Summary

Closes #653

Adds French (Français) as a fully supported UI and content language, enabling users in francophone countries (France, Switzerland, Belgium, Canada, etc.) to use Resume Matcher in their native language.

Changes

File	Change
apps/frontend/messages/fr.json	Complete French translation (620 keys, 1:1 parity with en.json)
apps/frontend/i18n/config.ts	Register 'fr' locale with name "Français" and flag
apps/frontend/lib/i18n/messages.ts	Import and register French messages
apps/backend/app/routers/config.py	Add "fr" to SUPPORTED_LANGUAGES

Translation notes

• Formal register (vous form) used throughout
• Technical terms preserved: API, LLM, PDF, GitHub, LinkedIn, etc.
• All placeholder variables ({count}, {date}, {status}, etc.) preserved
• Localized examples: Jean Dupont, +33 phone format, French city names
• "Resume" → "CV", "Cover Letter" → "Lettre de motivation", "Tailor" → "Adapter"

Test plan

• Set UI language to French in Settings — verify all UI strings render correctly
• Set content language to French — verify AI-generated content uses French
• Verify language selector shows "Français" with the French flag
• Switch between French and other languages — verify no missing keys or fallback to English
• Verify backend accepts "fr" as a valid language in /config/language endpoint

---

Summary by cubic

Adds full French (Français) support for both UI and generated content. Syncs backend language schema defaults to include fr and pt. Closes #653.

• New Features

  • Added fr.json with complete French translations (parity with en.json).
  • Registered 'fr' locale and flag in i18n config; loaded French messages in the frontend.
  • Added 'fr' to backend SUPPORTED_LANGUAGES.

• Bug Fixes

  • Synced LanguageConfig schema defaults and comments to include fr and pt, matching router supported languages.

^{Written for commit f8c76f0. Summary will update on new commits.}

[kilo-code-bot]

Code Review Summary

Status: 1 Issue Found | Recommendation: Address before merge

Overview

Severity	Count
CRITICAL	1
WARNING	0
SUGGESTION	0

Other Observations (not in diff)

Issues found in unchanged code that cannot receive inline comments:

File	Line	Issue
apps/backend/app/prompts/templates.py	4-10	CRITICAL: Missing French in LANGUAGE_NAMES dictionary. The dictionary maps language codes to full names for LLM prompts, but French ("fr") is not included. When a user selects French as their content language, get_language_name("fr") will return "English" (the fallback), causing the LLM to generate content in English instead of French. Add "fr": "French", to the LANGUAGE_NAMES dictionary.

Files Reviewed (5 files)

• apps/backend/app/routers/config.py - 0 new issues (existing comment about schema sync is now resolved in this PR)
• apps/backend/app/schemas/models.py - 0 issues
• apps/frontend/i18n/config.ts - 0 issues
• apps/frontend/lib/i18n/messages.ts - 0 issues
• apps/frontend/messages/fr.json - 0 issues (new file with French translations)

Notes

• The PR correctly adds French support to the frontend i18n configuration and backend API validation.
• The schema and router SUPPORTED_LANGUAGES are now properly synchronized (previous comment about this is resolved).
• Action Required: Update apps/backend/app/prompts/templates.py to include French in the LANGUAGE_NAMES dictionary to complete the i18n support for LLM-generated content.

Fix these issues in Kilo Cloud

[cubic-dev-ai]

1 issue found across 4 files

Prompt for AI agents (unresolved issues)

Check if these issues are valid — if so, understand the root cause of each and fix them. If appropriate, use sub-agents to investigate and fix each issue separately.


<file name="apps/backend/app/routers/config.py">

<violation number="1" location="apps/backend/app/routers/config.py:219">
P2: Schema and router constants are out of sync: `LanguageConfigResponse` has default `supported_languages=["en", "es", "zh", "ja"]` but router's `SUPPORTED_LANGUAGES` includes `["en", "es", "fr", "zh", "ja", "pt"]`. Update the schema default value and comments in `LanguageConfigRequest` to match the router's supported languages.</violation>
</file>

_{Reply with feedback, questions, or to request a fix. Tag @cubic-dev-ai to re-run a review.}