Swagger Try it out: render request-body properties as form fields #28

Problem

Swagger UI's "Try it out" renders JSON request bodies as one JSON editor. It only renders path/query/header parameters such as instanceName as separate input controls. Users want each request-body field exposed as its own labeled UI input.

Current state

The runtime OpenAPI document already contains per-property JSON Schemas, required fields, types, enums, bounds, and descriptions. This is not fixed by adding more schema annotations or toggling a standard Swagger UI option: upstream Swagger UI intentionally edits an application/json request body as one JSON value.

Required design

Add a custom request-body form renderer/plugin (or a separate API explorer) that:

• recursively renders object properties as controls
• supports required/optional fields, booleans, numbers, enums, arrays, nested objects, nullable values, patterns, bounds, examples, and oneOf/anyOf
• serializes the controls back to the exact JSON request body
• preserves the existing authorization, path parameters, response display, and normal JSON editor as an advanced/fallback mode
• works across all runtime-generated routes rather than hardcoding individual methods

Acceptance criteria

• instanceName remains a path field
• request-body properties appear as labeled controls for representative simple and nested routes
• controls respect schema validation and descriptions
• generated request JSON is identical to the documented body
• raw JSON remains available
• automated UI regression coverage exists for representative schemas

This is separate from missing schemas: the schemas are present; the missing piece is a custom Swagger UI renderer.