feat: implement automated ingestion pipeline with state persistence and add database maintenance utilities

feat: stabilize celery loops, add redis caching, and scale stage 2 neural limit to 250

refactor: unified session view, pipeline polling, db wipe

feat: add pipeline page, session delete with Qdrant cleanup, explain worker, and final frontend polish

fix: resolve asyncpg ssl connection errors and Qdrant strict payload filtering

feat: implement session-based candidate matching architecture

feat: add gap analysis, LLM explainer via Groq, and all API routes

feat: implement Stage 2 reranker with BGE cross-encoder and RRF fusion

feat: implement Stage 1 retriever - ANN search + structured weighted scorer

feat: implement feature builder with growth velocity and JD quality scoring

feat: add embedding singleton and batch ingest Celery worker

feat: define ORM models for JD, Candidate, MatchResult with Alembic migration

feat: scaffold FastAPI app with async Postgres and Qdrant connection