## Why
MCP callable namespaces and tool names can differ from their backend identities or match built-in tool names. Classifying calls by name can misidentify MCP calls and incorrectly parse namespaced `write_stdin` calls as terminal operations.
## What changed
Resolve `ToolCallKind::Mcp` from the runtime invocation's server and tool as soon as the runtime starts, before MCP correlation assignment. Preserve the caller-facing summary and raw invocation, and skip built-in runtime handling for MCP calls.
Only create dispatch-based `write_stdin` terminal operations for calls without a namespace.
## Testing
Add replay regression coverage for prefixed and unprefixed MCP aliases, names that match built-in tools, and `write_stdin` arguments with and without a session ID. Verify backend classification, preserved callable identity and dispatch lifecycle, and the absence of terminal operations and sessions.
GitOrigin-RevId: 71f31335c1eb36b6b7e1a34383d10fc500bd2c4f
cassirer-openai
3f31c0a040