Add packages/types/src/federation/ with Zod v4 schemas and inferred TS
types for the M3 federation wire protocol. Includes verbs constant,
request schema, list/get/capabilities response factories, _source tag
helper, and typed error envelope + exception hierarchy. 46 unit tests;
typecheck, lint, and format:check all green.
Closes#462
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
ac475d240d