Change log for 0.4.0 release (#204)

With Claude's help.

Author: gvanrossum-ms

CHANGELOG.md

@@ -1,5 +1,67 @@
 # Typeagent Change Log
 
+## 2026
+
+### 0.4.0 (March 3)
+
+Lots of improvements; the highlights are provider-agnostic model
+configuration backed by pydantic_ai, email ingestion, and a major
+infrastructure overhaul.
+
+#### Core typeagent package
+- Fixed a number of bugs that affected the core query algorithms
+- Provider-agnostic chat and embedding model configuration via new
+  `model_adapters` module backed by pydantic_ai (#200):
+  - Use `provider:model` spec strings,
+    e.g. `create_chat_model("openai:gpt-4o")`.
+  - Replace `AsyncEmbeddingModel` with `IEmbedder`/`IEmbeddingModel`
+    protocols and `CachingEmbeddingModel`.
+  - Add `OPENAI_MODEL` and `OPENAI_EMBEDDING_MODEL` envvars
+    to override the default chat and embedding models.
+- Split `interfaces.py` into separate modules
+  (`interfaces_core`, `_indexes`, `_search`, `_serialization`,
+  `_storage`) (Bernhard Merkle, #118).
+- Make remaining storage-provider APIs async
+  (`get/set_conversation_metadata`, `is_source_ingested`, etc.) (#196).
+- Fix listeners/recipients confusion in podcast metadata serialization (#174).
+- Implement `SqliteRelatedTermsIndex.serialize()` (Rajiv Singh, #115).
+
+#### Email
+- New _tools/ingest_email.py_ tool to ingest email
+  into a SQLite-backed conversation database (#111).
+- Add _tools/mail/outlook_dump.py_ to dump Outlook/Microsoft 365 email
+  via the Graph API (Bernhard Merkle, #199).
+- Add _tools/mail/mbox_dump.py_ to convert mbox files for ingestion
+  (Bernhard Merkle, #198).
+- Consolidate mail dump tools under _tools/mail/_ with shared
+  _README.md_ (Bernhard Merkle).
+- Various ergonomic improvements and fixes (#162, #168, #170).
+
+#### Tools
+- Add conversation history to _tools/query.py_ for
+  pronoun/reference resolution across multi-turn queries
+  (Rajiv Singh, #117).
+- Add _tools/load_json.py_ to load JSON-serialized index data
+  into a SQLite database; remove `--podcast` flag from
+  _tools/query.py_ (#164).
+
+#### Docs
+- Improve docs for Azure env vars (#175).
+- Add AgentCon 2026 presentation and demo videos
+  (Bernhard Merkle, #194, #202).
+- VS Code / Pyright plugin setup instructions
+  (Bernhard Merkle, #150).
+
+#### Infrastructure
+- Move _typeagent/_ to _src/typeagent/_ (Bernhard Merkle, #139).
+- Move tests and test data to _tests/_ directory (Bernhard Merkle, #144).
+- Move ancillary dirs into subdirs (Bernhard Merkle, #145).
+- Introduce `isort` for import sorting.
+- Make pyright error on unused variables and imports (#129).
+- Add readline support on Windows (#152, Bernhard Merkle).
+- Enhance release script to update _uv.lock_ and create release PR
+  (Rajiv Singh, #169).
+
 ## 2025
 
 ### 0.3.3 (Nov 25)