v0.4.0

## What's Changed
* doc: changelog for 0.3.0 by @nicoloboschi in https://github.com/vectorize-io/hindsight/pull/156
* doc: update expired Slack invite link by @cdbartholomew in https://github.com/vectorize-io/hindsight/pull/157
* feat: add cloud mode to skill installer for team memory sharing by @cdbartholomew in https://github.com/vectorize-io/hindsight/pull/158
* Fix skill installer test examples to use meaningful content by @cdbartholomew in https://github.com/vectorize-io/hindsight/pull/160
* feat(cli): accept more file types on retain-files by @nicoloboschi in https://github.com/vectorize-io/hindsight/pull/163
* feat: introduce mental models by @nicoloboschi in https://github.com/vectorize-io/hindsight/pull/132
* doc: refinement for 0.3.0 new features by @nicoloboschi in https://github.com/vectorize-io/hindsight/pull/159
* Add structured JSON logging support by @cdbartholomew in https://github.com/vectorize-io/hindsight/pull/170
* feat: improve mental model refresh and add directives by @nicoloboschi in https://github.com/vectorize-io/hindsight/pull/166
* chore: unify agents.md and claude.md by @nicoloboschi in https://github.com/vectorize-io/hindsight/pull/173
* fix(sec): upgrade vulnerable deps by @nicoloboschi in https://github.com/vectorize-io/hindsight/pull/174
* feat(clients): mental models api by @nicoloboschi in https://github.com/vectorize-io/hindsight/pull/172
* fix: pytorch init failures by @nicoloboschi in https://github.com/vectorize-io/hindsight/pull/175
* feat: new 'worker' service by @nicoloboschi in https://github.com/vectorize-io/hindsight/pull/176
* chore: drop unused access_count column by @nicoloboschi in https://github.com/vectorize-io/hindsight/pull/178
* fix: improve pytorch model initialization to prevent meta tensor issues by @nicoloboschi in https://github.com/vectorize-io/hindsight/pull/180
* fix: sometimes memories gets extracted in the wrong language by @nicoloboschi in https://github.com/vectorize-io/hindsight/pull/184
* fix: simplify pytorch model initialization to prevent meta tensor issues by @nicoloboschi in https://github.com/vectorize-io/hindsight/pull/185
* feat: revisit mental models, directives and reflections by @nicoloboschi in https://github.com/vectorize-io/hindsight/pull/179
* Fix Gemini tool response format by including function name by @cdbartholomew in https://github.com/vectorize-io/hindsight/pull/187
* feat(python-sdk): add tags filtering support to high-level client by @phamgialinhlx in https://github.com/vectorize-io/hindsight/pull/186
* feat: support for npx add-skill by @nicoloboschi in https://github.com/vectorize-io/hindsight/pull/191
* feat(mcp): add timestamp to retain by @nicoloboschi in https://github.com/vectorize-io/hindsight/pull/190
* fix: improve mental model consolidation by @nicoloboschi in https://github.com/vectorize-io/hindsight/pull/197
* feat(litellm): async retain, reflect support, and API cleanup by @DK09876 in https://github.com/vectorize-io/hindsight/pull/167
* Fix: Pass api_key to Hindsight client in litellm integration by @cdbartholomew in https://github.com/vectorize-io/hindsight/pull/193
* chore: versioned docs by @nicoloboschi in https://github.com/vectorize-io/hindsight/pull/198
* doc: mental models by @nicoloboschi in https://github.com/vectorize-io/hindsight/pull/199
* ci: add upgrade tests by @nicoloboschi in https://github.com/vectorize-io/hindsight/pull/200
* fix(ui): reflections based on don't show up all contents by @nicoloboschi in https://github.com/vectorize-io/hindsight/pull/203
* feat(litellm): support tags and mission in litellm package by @nicoloboschi in https://github.com/vectorize-io/hindsight/pull/202
* chore: internal renames by @nicoloboschi in https://github.com/vectorize-io/hindsight/pull/204
* fix: include tags, created_at, proof_count in graph table_rows by @cdbartholomew in https://github.com/vectorize-io/hindsight/pull/207
* fix: multi-tenant schema context for worker task execution by @cdbartholomew in https://github.com/vectorize-io/hindsight/pull/208
* chore: drop dead code by @nicoloboschi in https://github.com/vectorize-io/hindsight/pull/210
* fix: misc fixes for observations and mental models by @nicoloboschi in https://github.com/vectorize-io/hindsight/pull/209
* chore: cleanup benchmarks runner with old flags by @nicoloboschi in https://github.com/vectorize-io/hindsight/pull/212
* feat: add custom extraction prompt by @nicoloboschi in https://github.com/vectorize-io/hindsight/pull/213
* fix: graph endpoint not showing links for observations by @nicoloboschi in https://github.com/vectorize-io/hindsight/pull/214
* fix(embed): daemon process XPC connection crash on macos by @nicoloboschi in https://github.com/vectorize-io/hindsight/pull/215


**Full Changelog**: https://github.com/vectorize-io/hindsight/compare/v0.3.0...v0.4.0