v1.9.1

<!-- Release notes generated using configuration in .github/release.yml at main -->

## What's Changed
### ✨ New Features
* feat: Enhance config loading by applying `GUNICORN_CMD_ARGS` before programmatic options by @severfire in https://github.com/langflow-ai/langflow/pull/12313
* feat: filter out live connections from wxo adapter by @HzaRashid in https://github.com/langflow-ai/langflow/pull/12744
* feat(deployments): filter WXO agent list to drafts when `load_from_provider=true` by @HzaRashid in https://github.com/langflow-ai/langflow/pull/12745
* feat(google): refresh Gemini model list and enable tool calling for Gemini 3 by @erichare in https://github.com/langflow-ai/langflow/pull/12797
* feat: e2e tests for deployments api by @HzaRashid in https://github.com/langflow-ai/langflow/pull/12767

### 🐛 Bug Fixes
* fix(frontend): filter duplicate draft/live connections in deploy modal by @viktoravelino in https://github.com/langflow-ai/langflow/pull/12724
* fix(custom): honor asname in `from X import Y as Z` for custom components by @erichare in https://github.com/langflow-ai/langflow/pull/12813
* fix(mcp): close path traversal + cross-user disclosure (PVR0754098) by @erichare in https://github.com/langflow-ai/langflow/pull/12818
* fix: db guards for deployments by @HzaRashid in https://github.com/langflow-ai/langflow/pull/12339
* fix(traces): serialize enum values for PostgreSQL on trace/span tables by @erichare in https://github.com/langflow-ai/langflow/pull/12820
* fix: preserve spaces in shareable playground chat input by @Cristhianzl in https://github.com/langflow-ai/langflow/pull/12833
* fix(security): require auth on deprecated `/api/v1/upload/{flow_id}` by @erichare in https://github.com/langflow-ai/langflow/pull/12831
* fix: prevent XSS in chat messages with `rehype-sanitize` by @Jkavia in https://github.com/langflow-ai/langflow/pull/12718
* fix(security): close IDOR in `get_flow_by_id_or_endpoint_name` (LE-639) by @erichare in https://github.com/langflow-ai/langflow/pull/12832
* fix(security): default `WEBHOOK_AUTH_ENABLE` to `True` by @erichare in https://github.com/langflow-ai/langflow/pull/12845
* fix: route memory ops to stubs when DB service is noop by @jordanrfrazier in https://github.com/langflow-ai/langflow/pull/12808
* fix: allow backend/frontend Docker builds when main version exists by @vjgit96 in https://github.com/langflow-ai/langflow/pull/12854

### 📝 Documentation Updates
* docs: clarify autosaving and versioned flow saving by @mendonk in https://github.com/langflow-ai/langflow/pull/12794
* docs: add multi-model opensearch component by @mendonk in https://github.com/langflow-ai/langflow/pull/12799
* docs: wxo feature by @mendonk in https://github.com/langflow-ai/langflow/pull/12677
* docs: clarify trace storage when multiple providers are enabled by @mendonk in https://github.com/langflow-ai/langflow/pull/12816
* docs: concatenate and merge options for dataframe operations component by @mendonk in https://github.com/langflow-ai/langflow/pull/12835
* docs: tip for running local ollama models by @mendonk in https://github.com/langflow-ai/langflow/pull/12840

### 🛠 Maintenance Tasks
* refactor: Center truncate deployment provider URL by @a-effort in https://github.com/langflow-ai/langflow/pull/12579
* chore: upgrade wxo adk to 2.8.0 by @HzaRashid in https://github.com/langflow-ai/langflow/pull/12707
* ref: removes retries from wxo api calls by @jordanrfrazier in https://github.com/langflow-ai/langflow/pull/12770
* ref: set wxo ff to true by default by @jordanrfrazier in https://github.com/langflow-ai/langflow/pull/12826
* fix(ci): prevent duplicate tags and validate tag format in release workflow by @vjgit96 in https://github.com/langflow-ai/langflow/pull/12847
* chore: security patch by @Adam-Aghili in https://github.com/langflow-ai/langflow/pull/12725

### ✅ Tests
* test: add missing test coverage for wxo deployments by @jordanrfrazier in https://github.com/langflow-ai/langflow/pull/12689
* fix: Update signature for WXO tests by @erichare