Phase 0 foundation: canonical schema, ingest pipeline, CRM MCP server

Workstream A–C substrate for the Ten31 agentic system:
- A1: docs/crm-overview.md; CLAUDE.md conventions + guardrail #9
- A2: additive/reversible core migration (canonical_entities, entity_links,
  interaction_log, relationship_edges, soft-delete) + ledgered runner
- B1/B3: chunking + deterministic entity resolution (backend/ingest)
- B2: dense (bge-m3) + BM25 sparse ingest to Qdrant crm_chunks
- C: CRM MCP server (reads, retrieval modes, logged writes) — no outbound tools
- docs: redaction/re-hydration, Gmail enablement runbook
- synthetic test data; .env.example; housekeeping (.gitignore, untrack crm.db,
  drop legacy files + start9/0.3.5)

Verified end-to-end on synthetic data + live Sparks (hybrid > dense on entity
queries). Real backfill runs on Ten31 infra; index holds synthetic data only.
Branch snapshot also captures pre-existing working-tree changes.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

backend/ingest/config.py

@@ -0,0 +1,28 @@
+"""Ingest config — loads .env and exposes the Spark/Qdrant/CRM settings."""
+import os
+
+_ROOT = os.path.dirname(os.path.dirname(os.path.dirname(os.path.abspath(__file__))))
+
+
+def load_env(path=None):
+    path = path or os.path.join(_ROOT, ".env")
+    if not os.path.exists(path):
+        return
+    with open(path, "r", encoding="utf-8") as fh:
+        for line in fh:
+            line = line.strip()
+            if not line or line.startswith("#") or "=" not in line:
+                continue
+            k, v = line.split("=", 1)
+            os.environ.setdefault(k.strip(), v.strip())
+
+
+load_env()
+
+SPARK_CONTROL_URL = os.environ.get("SPARK_CONTROL_URL", "").rstrip("/")
+SPARK_VERIFY_TLS = os.environ.get("SPARK_CONTROL_VERIFY_TLS", "false").lower() in ("1", "true", "yes", "on")
+QDRANT_URL = os.environ.get("QDRANT_URL", "").rstrip("/")
+COLLECTION = os.environ.get("CRM_QDRANT_COLLECTION", "crm_chunks")
+EMBED_MODEL = os.environ.get("CRM_EMBED_MODEL", "BAAI/bge-m3")
+DENSE_DIM = int(os.environ.get("CRM_EMBED_DIM", "1024"))
+DEFAULT_DB = os.environ.get("CRM_DEV_DB_PATH", os.path.join(_ROOT, "data", "crm_dev.db"))