v0.11.0

Added

• Thread-index cap + ?limit (AGH-1). GET threads/ returns at most
  DJANGO_AG_UI["THREAD_LIST_LIMIT"] rows (default 200); the client may request
  fewer via ?limit=N and a larger value is clamped to the ceiling, so a user
  with thousands of threads no longer fetches and serializes all of them per
  drawer open. ConversationStore.list gains a limit argument.
• ConversationStore.exists() (AGH-1). A cheap owner-scoped presence check
  (no message body loaded). The rename endpoint now probes it instead of loading
  and deserializing the whole thread just to 404. Model-backed stores answer with
  a metadata-only .exists() query.

Changed (breaking)

• OpenedAttachment.content is now an open readable stream, not bytes
  (AGH-3). Downloads stream the file via FileResponse instead of buffering it
  whole in memory, so a large attachment (with the size cap disabled) no longer
  lands in memory. AttachmentStore.open returns the open handle; the download
  view and the read_attachment tool consume/close it. A custom
  AttachmentStore that built OpenedAttachment(content=<bytes>) must now pass a
  readable binary handle.
• ConversationStore gains required exists() and a limit on list(). A
  custom store implementation must add exists() and accept limit= on list().

Fixed

• Rename / upload title & filename caps (AGH-1). A PATCH threads/<id>/
  title longer than the model's CharField(max_length=255) is truncated rather
  than raising a database DataError on a strict backend. (Uploaded filenames
  were already truncated to 255 by Django's UploadedFile.)
• Cross-toolset name-collision guard (AGH-2). The drf-mcp, SpecToolset, and
  read_attachment toolset builders previously each excluded only the @tool
  registry's names, so if DRF_MCP_SERVER and SERVICE_SPECS exposed the same
  tool name (or either exposed read_attachment), pydantic-ai raised a duplicate
  UserError mid-run while the catalog looked clean. One seen set is now
  threaded through all three builders in build_tool_catalog's precedence order
  (registry → drf-mcp → spec → attachment) so a duplicate can't reach the run.
• Early upload abort (AGH-3). A CappedUploadHandler aborts an oversized
  upload mid-parse (honoring ATTACHMENT_MAX_BYTES) instead of spooling the whole
  body to a temp file before the 413.
• Transcription client reuse + timeout (AGH-3). OpenAITranscriptionBackend
  caches its AsyncOpenAI client on the instance rather than constructing one
  (with a new connection pool) per call, and sets a bounded default timeout
  (60 s, overridable) instead of the SDK's 10-minute default.