feat: Map ZodTuple to a fixed-length array schema

[razor-x]

Tuples fell through to catchAllParser, so a z.tuple() field emitted an empty schema with no type. Downstream tooling then has nothing to work with — the Seam blueprint generator skips any property whose schema lacks a type, so tuple fields silently dropped out of the API documentation:

The created_between property for /seam/console/v1/timelines/get will not be documented since it does not define a type.
The enforced_setpoint_range_celsius property for device.properties.sensi_metadata will not be documented since it does not define a type.

OpenAPI 3.0 has no positional item schemas, so a tuple becomes a fixed-length array whose items accept every position's schema — a single schema when the positions agree, otherwise a oneOf. A .rest() type contributes its schema and drops maxItems, since a variadic tuple has no upper bound. prefixItems would describe the positions exactly, but it is OpenAPI 3.1 only, and consumers such as seam-connect emit openapi: "3.0.0" and lint the result, so emitting it would produce specs their tooling rejects.

Generated schemas, from the three fields added to the example app's /api/todo/add body:

Zod	OpenAPI
z.tuple([z.string().datetime(), z.string().datetime()])	{type: "array", items: {type: "string", format: "date-time"}, minItems: 2, maxItems: 2}
z.tuple([z.number(), z.string()])	{type: "array", items: {oneOf: [{type: "number", format: "float"}, {type: "string"}]}, minItems: 2, maxItems: 2}
z.tuple([z.string()]).rest(z.string())	{type: "array", items: {type: "string"}, minItems: 1}

getTupleRest is added to the zod compat layer alongside the existing getTupleItems; both Zod 3 and Zod 4 keep the rest type at def.rest, so the existing getDef split covers it.

zod-to-ts already handled ZodTuple, so the generated TypeScript types are unchanged — this only affects the OpenAPI output.

Testing

• yarn workspace nextlove build, typecheck, and test (8 tests) pass.
• Example-app OpenAPI generation tests pass (9 tests), including three new assertions covering the homogeneous, heterogeneous, and variadic cases above.

---

Generated by Claude Code