Advisor review of the prior commit (5269b7d) found the except TimeoutError
branch was wider than the brief asked for: builtin TimeoutError is also
socket.timeout (3.10+) and asyncio.TimeoutError (3.11+), so any TimeoutError
reaching that clause got relabeled mcp_timeout regardless of source. Gate on
anyio.CancelScope.cancelled_caught instead, mirroring _unwrap_ingest_error's
ownership rule (own it, wrap it; otherwise, untouched).
Measured: no live trigger exists today (MCP's own internal read-timeout
converts to McpError before reaching us; a server-side TimeoutError becomes
an ordinary isError result) -- pinned with a synthetic test raising from
StdioServerParameters construction, inside our fail_after scope but before
either nested task group, so it arrives ungrouped. Four mutations red against
the full 625-test suite: drop the translation, revert to asyncio.wait_for,
relabel the code, and drop the cancelled_caught gate.
Also promotes anyio to a declared direct dependency (was transitive via mcp
only) -- ingest_mcp.py now imports it directly.