fix: M4 Phase 1 bugs - dev.chunks refs, search_path, uuid column

Bug fixes from M4 report:
- 4 remaining dev.chunks → dev.chunk in SQL queries
- search_path includes public for pgvector extension
- get_chunk_by_chunk_id_and_uuid: uuid → file_uuid
- New endpoint: GET /api/v1/file/:uuid/chunk/:chunk_id

docs_v1.0/M4_HANDOVER/INDEX.md

@@ -0,0 +1,72 @@
+# M4 Handover Package — Complete
+
+## Contents
+
+| File | Size | Description |
+|------|:----:|-------------|
+| `HANDOVER_V2.0.md` | 9.6K | Main handover document |
+| `api_test.sh` | 8.7K | API smoke test (37 endpoints) |
+| `M4_RESPONSE.md` | 1.0K | M4 response (this file) |
+
+### Source Code (choose one)
+
+| File | Size | Description |
+|------|:----:|-------------|
+| `momentry_core_v1.0.1_source.tar.gz` | 204M | Git archive (latest commit) |
+| `momentry_core.bundle` | 150M | Git bundle (full repo, `git clone momentry_core.bundle`) |
+
+### DB Backup (pre-migration)
+
+| File | Size | Description |
+|------|:----:|-------------|
+| `dev.chunks.sql` | 20M | `dev.chunks` table (old schema, pre-migration) |
+| `dev.chunk_vectors.sql` | 56M | `dev.chunk_vectors` table (pre-migration) |
+
+### Scripts
+
+| File | Description |
+|------|-------------|
+| `generate_asr1.py` | Generate correction record from DB + asr.json |
+| `apply_asr_corrections.py` | Apply corrections, preserve chunk_vectors |
+| `clean_sentence_text.py` | LLM cleaning + Qdrant re-embedding |
+| `pipeline_status.py` | Pipeline health check (9 stages) |
+| `split_asr_segments.py` | Sub-window speaker change detection |
+
+## Quick Start (on M4 machine)
+
+```bash
+# 1. Restore DB
+psql -U accusys -d momentry < dev.chunks.sql
+psql -U accusys -d momentry < dev.chunk_vectors.sql
+
+# 2. Apply schema migration
+psql -U accusys -d momentry -c "
+  ALTER TABLE dev.chunks RENAME TO dev.chunk;
+  ALTER TABLE dev.chunk DROP COLUMN IF EXISTS old_chunk_id;
+  ALTER TABLE dev.chunk DROP COLUMN IF EXISTS chunk_index;
+"
+psql -U accusys -d momentry -c "
+  UPDATE dev.chunk SET chunk_id = substring(chunk_id from 34)
+  WHERE chunk_id LIKE (file_uuid || '_%');
+  UPDATE dev.chunk_vectors cv SET chunk_id = substring(cv.chunk_id from 34)
+  FROM dev.chunk c WHERE c.file_uuid = cv.uuid AND cv.chunk_id LIKE (c.file_uuid || '_%');
+"
+
+# 3. Get source code
+git clone momentry_core.bundle momentry_core_0.1
+# or: tar xzf momentry_core_v1.0.1_source.tar.gz
+
+# 4. Apply corrections
+python3 generate_asr1.py
+python3 apply_asr_corrections.py
+
+# 5. Rebuild Qdrant
+python3 clean_sentence_text.py
+
+# 6. Build and run
+cargo build --bin momentry_playground
+DATABASE_SCHEMA=dev ./target/debug/momentry_playground server --port 3003
+
+# 7. Run API test
+bash api_test.sh
+```