v1.9.4

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

## What's Changed
### 🐛 Bug Fixes
* fix: Model handling for tool calling in agents and update IBM models by @mfortman11 in https://github.com/langflow-ai/langflow/pull/13191
* fix(ci): backport bundle rename step to nightly workflow on main by @erichare in https://github.com/langflow-ai/langflow/pull/13195
* fix(ci): gate nightly release on successful tag creation by @erichare in https://github.com/langflow-ai/langflow/pull/13198
* fix(ci): use local bundle wheels in nightly install tests by @erichare in https://github.com/langflow-ai/langflow/pull/13256
* fix: properly set nightly-base skipped by @Adam-Aghili in https://github.com/langflow-ai/langflow/pull/13338
### 📝 Documentation Updates
* docs: rewrite AGENTS.md as hub with topical project philosophy docs by @ogabrielluiz in https://github.com/langflow-ai/langflow/pull/13038
### 🛠 Maintenance Tasks
* refactor(settings): split monolithic Settings into per-domain group mixins by @ogabrielluiz in https://github.com/langflow-ai/langflow/pull/13141
### Others
* chore(ci): timeout bump + harden langflow grep + build/publish src/bundles/* wheels by @erichare in https://github.com/langflow-ai/langflow/pull/13199
* ci: stop publishing -nightly bundle variants; release bundles on demand by @erichare in https://github.com/langflow-ai/langflow/pull/13206
* ci(release_bundles): build lfx wheel locally for smoke test by @erichare in https://github.com/langflow-ai/langflow/pull/13207
* ci(nightly): re-pin bundle lfx deps to lfx-nightly during nightly build by @erichare in https://github.com/langflow-ai/langflow/pull/13208


**Full Changelog**: https://github.com/langflow-ai/langflow/compare/1.9.3...1.9.4

<!-- Release notes generated using configuration in .github/release.yml at v1.9.4 -->

## What's Changed
### ✨ New Features
* feat: add DB migration validation workflow (LE-1259) [backport 1.9.4] by @vjgit96 in https://github.com/langflow-ai/langflow/pull/13348
### 🐛 Bug Fixes
* fix: upgrade dependencies for security fixes by @Jkavia in https://github.com/langflow-ai/langflow/pull/13218
* fix: Update package to safer version to address the CVEs by @Jkavia in https://github.com/langflow-ai/langflow/pull/13270
* fix: use langchain-mongodb and langchain-qdrant. Port mem0 update by @Adam-Aghili in https://github.com/langflow-ai/langflow/pull/13329
* fix: port chroma collection hardening by @erichare in https://github.com/langflow-ai/langflow/pull/13339
### Others
* chore: port Remove the diskcache dependency by @Adam-Aghili in https://github.com/langflow-ai/langflow/pull/13334
* chore: port pre-create LANGFLOW_CONFIG_DIR #13212 by @Adam-Aghili in https://github.com/langflow-ai/langflow/pull/13342


**Full Changelog**: https://github.com/langflow-ai/langflow/compare/v1.9.3...v1.9.4