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/figure_processor.py

@@ -0,0 +1,78 @@
+"""Persists Docling figures to PostgreSQL + MinIO (caption + optional crop)."""
+
+from __future__ import annotations
+
+import uuid
+
+from sqlalchemy import select
+
+from app.db.models import ArtifactType, DocumentArtifact, Figure
+from app.ingestion.docling_extractor import ExtractedFigure
+from app.logging_config import get_logger
+from app.storage.local_paths import key_figure_crop
+from app.storage.minio_client import MinioStorage
+
+logger = get_logger(__name__)
+
+
+def persist_figures(
+    db,
+    storage: MinioStorage,
+    document_id: uuid.UUID,
+    figures: list[ExtractedFigure],
+    page_id_by_number: dict[int, uuid.UUID],
+) -> int:
+    count = 0
+    for f in figures:
+        existing = db.execute(
+            select(Figure).where(Figure.document_id == document_id, Figure.figure_index == f.figure_index)
+        ).scalar_one_or_none()
+        if existing is None:
+            existing = Figure(
+                document_id=document_id,
+                page_id=page_id_by_number.get(f.page_number),
+                page_number=f.page_number,
+                figure_index=f.figure_index,
+            )
+            db.add(existing)
+
+        existing.caption = f.caption
+        existing.description = (
+            f"Figure detected on page {f.page_number}." if not f.caption else
+            f"Figure on page {f.page_number}. Caption: {f.caption}"
+        )
+
+        if f.image_bytes:
+            key = key_figure_crop(document_id, f.page_number, f.figure_index)
+            storage.put_bytes(
+                bucket=storage.derived_bucket,
+                key=key,
+                data=f.image_bytes,
+                content_type=f"image/{f.image_ext}",
+            )
+            existing.storage_bucket = storage.derived_bucket
+            existing.storage_key = key
+            _ensure_artifact(db, document_id, ArtifactType.FIGURE_CROP, storage.derived_bucket, key, f.page_number)
+
+        count += 1
+    return count
+
+
+def _ensure_artifact(db, document_id: uuid.UUID, artifact_type: str, bucket: str, key: str, page: int | None) -> None:
+    existing = db.execute(
+        select(DocumentArtifact).where(
+            DocumentArtifact.document_id == document_id,
+            DocumentArtifact.storage_key == key,
+        )
+    ).scalar_one_or_none()
+    if existing:
+        return
+    db.add(
+        DocumentArtifact(
+            document_id=document_id,
+            artifact_type=artifact_type,
+            storage_bucket=bucket,
+            storage_key=key,
+            page_number=page,
+        )
+    )