docs: add standardized comments to all services (Python, Go, Bash)

- Add docs/commenting-standard.md defining per-language comment standards
  (Go godoc, Python PEP-257, C Doxygen, Bash header blocks, SQL banners)

- services/dashboard: 100% docstring coverage (100/100 functions)
  - All FastAPI route handlers, helpers, classes, and models documented
  - Language: French (project convention)

- services/bot-detector: 100% docstring coverage (53/53 symbols)
  - bot_detector.py: 14 functions + module docstring
  - anubis/fetch_rules.py: 9 functions

- shared/python/ja4_common: full docstrings on ClickHouseClient (7 methods)
  and ClickHouseSettings class

- services/correlator: 24 godoc comments added across 6 Go files
  - correlation_service.go: 10 private helpers
  - unixsocket/source.go: 6 parsing/socket helpers
  - correlated_log.go: 4 field extraction helpers
  - orchestrator.go, logger.go, main.go: 4 comments

- services/correlator/scripts/audit-architecture.sh: standardized header block

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

services/dashboard/backend/routes/fingerprints.py

@@ -489,6 +489,7 @@ async def get_ua_analysis(
 
 
 def _build_ua_risk_flags(ua: str, ua_type: str, unique_ja4s: int, ip_count: int) -> list:
+    """Construit la liste des indicateurs de risque pour un User-Agent."""
     flags = []
     if ua_type == "bot":
         flags.append("ua_bot_signature")