chore: bootstrap repository with governance docs

Initialize git, add Apache-2.0 LICENSE, .gitattributes (LF line
endings), AGENTS.md (entry points, stack, discovery order, baseline
checks), RUNBOOK.md (dev boot, prod deploy with overlay, ingestion,
failures, rollback, scaling notes), .env.prod.example with rotated
credential placeholders, and dev-only warnings on .env.example.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

app/utils/language.py

@@ -0,0 +1,24 @@
+"""Language detection helper - tolerant to short / mixed text."""
+
+from __future__ import annotations
+
+from langdetect import DetectorFactory, LangDetectException, detect_langs
+
+DetectorFactory.seed = 42
+
+
+def detect_language(text: str, min_chars: int = 40) -> str | None:
+    """Return ISO 639-1 language code or ``None`` if undetectable."""
+    if not text or len(text.strip()) < min_chars:
+        return None
+    try:
+        ranked = detect_langs(text)
+    except LangDetectException:
+        return None
+    if not ranked:
+        return None
+    return ranked[0].lang
+
+
+def has_cyrillic(text: str) -> bool:
+    return any("Ѐ" <= ch <= "ӿ" for ch in text)