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/ingestion/quality.py

@@ -0,0 +1,41 @@
+"""Quality flag computation for chunks."""
+
+from __future__ import annotations
+
+from typing import Any
+
+from app.utils.text_cleaning import looks_garbled
+
+LOW_OCR_CONFIDENCE_THRESHOLD = 0.6
+SHORT_TEXT_THRESHOLD = 24
+
+
+def compute_quality_flags(
+    *,
+    text: str,
+    block_type: str,
+    ocr_confidence: float | None,
+    has_handwriting: bool = False,
+) -> dict[str, Any]:
+    flags: dict[str, Any] = {
+        "low_ocr_confidence": False,
+        "very_short_text": False,
+        "possible_garbled_text": False,
+        "table_detected": block_type == "table",
+        "figure_detected": block_type in ("figure_caption", "figure_description"),
+        "handwriting_detected": has_handwriting or block_type == "handwriting",
+        "needs_manual_review": False,
+    }
+    if ocr_confidence is not None and ocr_confidence < LOW_OCR_CONFIDENCE_THRESHOLD:
+        flags["low_ocr_confidence"] = True
+    if text and len(text.strip()) < SHORT_TEXT_THRESHOLD:
+        flags["very_short_text"] = True
+    if looks_garbled(text):
+        flags["possible_garbled_text"] = True
+    if (
+        flags["low_ocr_confidence"]
+        or flags["possible_garbled_text"]
+        or flags["handwriting_detected"]
+    ):
+        flags["needs_manual_review"] = True
+    return flags