[TS SDK] Consolidate the duplicate sort and pagination param schemas #1130

Summary

SortQueryParamsSchema and SortBodyParamsSchema (sorting.ts:23 and :39) have identical shapes. Same for PaginatedQueryParamsSchema and PaginatedBodyParamsSchema. The split adds no type safety.

One caveat to resolve first: if we auto-generate schemas from TypeSpec later, a single shared schema may be hard to maintain. Zod does not distinguish query from body params, but TypeSpec does. Consolidating in Zod without a matching approach in the core library could create drift.

Acceptance criteria

• The TypeSpec query-vs-body distinction is evaluated, and the approach either consolidates in the core library too or documents why the SDK can diverge
• Each query/body pair shares one internal schema definition, or a concrete validation difference is implemented and tested to justify separate definitions
• The existing query and body schema exports remain available and continue to pass parity tests against their corresponding generated TypeSpec schemas
• Any Core or TypeScript SDK changes resulting from the decision are included in the [Core] v0.6.0 release and [TS SDK] v0.10.0 release candidates, respectively

Release coordination

This ticket may affect Core and the TypeScript SDK. GitHub allows only one milestone per issue, so [Core] v0.6.0 release is the primary planning milestone and [TS SDK] v0.10.0 release is the coordinated secondary release. If the decision does not require Core consolidation or a public SDK behavior change, one or both releases may not be necessary; update the milestone and release implications to match the recorded decision before closing the ticket.