fix: serve_chat endpoint bug, stale docs, and license mismatch

- Fix /serve/chat AttributeError: split Request and ChatRequest params
  so auth headers are read from HTTP request, not Pydantic body
- Add regression tests for the serve_chat endpoint bug
- Add agent_core and lightning to pyproject.toml wheel includes
- Replace Apache 2.0 LICENSE with MIT to match pyproject.toml
- Update test count from "228" to "600+" across README, docs, AGENTS.md
- Add 5 missing subsystems to README table (Spark, Creative, Tools,
  Telegram, agent_core/lightning)
- Update AGENTS.md project structure with 6 missing modules
- Mark completed v2 roadmap items (personas, MCP tools) in AGENTS.md

https://claude.ai/code/session_01GMiccXbo77GkV3TA69x6KS

pyproject.toml

@@ -87,6 +87,8 @@ include = [
     "src/spark",
     "src/tools",
     "src/creative",
+    "src/agent_core",
+    "src/lightning",
 ]
 
 [tool.pytest.ini_options]