feat: enforce greet(name) input bounds via pydantic.Field#19
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Audit (2026-05-01, P2.16): the TS sibling validates greet's name with Zod (1–200 chars). Python equivalent was untyped — empty strings and megastring inputs reached the handler. Switch the parameter annotation from `name: str` to `name: Annotated[str, Field(min_length=1, max_length=200, description=...)]`. FastMCP picks up the Annotated metadata and emits the constraint into the tool's JSON schema, so violations are rejected at protocol level. Tests pass; mypy strict still clean.
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From the 2026-05-01 audit (P2.16). Restores parity with the TS sibling's Zod constraint.
Switch from bare
name: strto:FastMCP propagates the
Fieldmetadata into the JSON schema; protocol layer rejects empty / oversized inputs before the handler runs.Test plan