feat: standalone claude-memory-mcp with multi-user support and Vault integration

Extracted from private infra repo into standalone open-source project.

Three operating modes:
- Local: SQLite + FTS5 (zero dependencies)
- Server: PostgreSQL via HTTP API with multi-user auth
- Full: PostgreSQL + HashiCorp Vault for secret management

Features:
- MCP stdio server with 5 tools (store/recall/list/delete/secret_get)
- FastAPI HTTP API with multi-user Bearer token auth (API_KEYS JSON map)
- Regex-based credential detection with auto-redaction
- AES-256-GCM encryption fallback for non-Vault deployments
- Vault KV v2 client (stdlib urllib, K8s SA auto-auth)
- Per-user data isolation (all queries scoped by user_id)
- Secret migration endpoint for existing plain-text credentials
- Backward-compatible env var aliases (CLAUDE_MEMORY_API_URL)

Infrastructure:
- Docker + docker-compose (API + PostgreSQL + optional Vault)
- Woodpecker CI (test → build → push → kubectl deploy)
- GitHub Actions CI (Python 3.11/3.12/3.13) + Release (GHCR + PyPI)
- Helm chart + raw Kubernetes manifests

96 tests passing across 6 test files.

.woodpecker.yml

@@ -0,0 +1,43 @@
+when:
+  - event: push
+    branch: main
+
+clone:
+  git:
+    image: woodpeckerci/plugin-git
+    settings:
+      attempts: 5
+      backoff: 10s
+
+steps:
+  - name: test
+    image: python:3.12-slim
+    commands:
+      - pip install -e ".[api,dev]"
+      - ruff check src/ tests/
+      - pytest tests/ -v --tb=short
+
+  - name: build-and-push
+    image: woodpeckerci/plugin-docker-buildx
+    depends_on:
+      - test
+    settings:
+      username: viktorbarzin
+      password:
+        from_secret: dockerhub-token
+      repo: viktorbarzin/claude-memory-mcp
+      dockerfile: docker/Dockerfile
+      context: .
+      platforms:
+        - linux/amd64
+      tags:
+        - "${CI_PIPELINE_NUMBER}"
+        - latest
+
+  - name: deploy
+    image: bitnami/kubectl:latest
+    depends_on:
+      - build-and-push
+    commands:
+      - kubectl rollout restart deployment/claude-memory -n claude-memory
+      - kubectl rollout status deployment/claude-memory -n claude-memory --timeout=120s