feat: Complete MongoDB/MinIO removal and integrate CLI consolidation

This commit completes the MongoDB and MinIO removal from the StellaOps
platform and integrates the CLI consolidation work from remote.

## Infrastructure Changes

- PostgreSQL v16+ is now the ONLY supported database
- Valkey v8.0 replaces Redis for caching, DPoP security, and event streams
- RustFS is the primary object storage (MinIO fully removed)
- NATS is OPTIONAL for messaging (Valkey is default transport)

## Docker Compose Updates

Updated all deployment profiles:
- deploy/compose/docker-compose.dev.yaml
- deploy/compose/docker-compose.airgap.yaml
- deploy/compose/docker-compose.stage.yaml
- deploy/compose/docker-compose.prod.yaml

All profiles now use PostgreSQL + Valkey + RustFS stack.

## Environment Configuration

Updated all env.example files with:
- Removed: MONGO_*, MINIO_* variables
- Added: POSTGRES_*, VALKEY_* variables
- Updated: SCANNER_QUEUE_BROKER to use Valkey by default
- Enhanced: Surface.Env and Offline Kit configurations

## Aoc.Cli Changes

- Removed --mongo option entirely
- Made --postgres option required
- Removed VerifyMongoAsync method
- PostgreSQL is now the only supported backend

## CLI Consolidation (from merge)

Integrated plugin architecture for unified CLI:
- stella aoc verify (replaces stella-aoc)
- stella symbols (replaces stella-symbols)
- Plugin manifests and command modules
- Migration guide for users

## Documentation Updates

- README.md: Updated deployment workflow notes
- DEVELOPER_ONBOARDING.md: Complete Valkey-centric flow diagrams
- QUICKSTART_HYBRID_DEBUG.md: Removed MongoDB/MinIO references
- VERSION_MATRIX.md: Updated infrastructure dependencies
- CLEANUP_SUMMARY.md: Marked all cleanup tasks complete
- 07_HIGH_LEVEL_ARCHITECTURE.md: Corrected infrastructure stack
- 11_DATA_SCHEMAS.md: Valkey keyspace documentation

## Merge Resolution

Resolved merge conflicts by accepting incoming changes which had more
complete Surface.Env and Offline Kit configurations.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

README.md

@@ -28,9 +28,9 @@ Detailed operator guidance is available in `docs/10_CONCELIER_CLI_QUICKSTART.md`
 command reference material lives in `docs/09_API_CLI_REFERENCE.md`.
 
 Pipeline note: deployment workflows should template `etc/concelier.yaml` during CI/CD,
-injecting environment-specific Mongo credentials and telemetry endpoints. Upcoming
-releases will add Microsoft OAuth (Entra ID) authentication support—track the quickstart
-for integration steps once available.
+injecting environment-specific PostgreSQL connection strings and telemetry endpoints.
+Upcoming releases will add Microsoft OAuth (Entra ID) authentication support—track
+the quickstart for integration steps once available.
 
 ## Documentation