fix(analyzer): inline bodies of the same shape took a type name from another operation

[giraffesyo]

Closes #125.

What was wrong

Synthesized types are keyed on shape, so two operations that each write the same body inline collapse onto one type, named for whichever the analyzer converted first. Seven single-file upload endpoints all took UploadStandaloneAiChatAttachmentBody.

The same dedup hits inline response bodies, so an operation could return a type named for a different endpoint. #125 assumed output types were already distinct; that holds only because huma emits those response schemas as named components. Untitled inline ones collapse the same way.

The fix

A body an operation writes inline now scopes what it synthesizes. Inside that scope the shape key is prefixed with the body, so each operation gets its own type named for itself. The scope covers the whole subtree, so a nested inline object does not leak one operation's name into another's signature either. Applied to request bodies, response bodies, SSE event payloads, and webhook and callback payloads.

Bodies the spec names stay shared:

• a $ref to components/requestBodies or components/responses (checked with GoLow().IsReference())
• a title: on the inline schema, or an external-file $ref, both of which already self-name
• component schemas and everything outside an operation body

An event stream resolves one schema twice, as the response body and as the event payload. Keying on each name hint split that into two identical types, so the key is the body rather than the hint and StreamEventsResponse stays one type.

Tests

• internal/analyzer/schemas_operation_body_test.go: per-operation naming for request and response, component $ref bodies stay shared, titled bodies stay shared, an event payload declares one type.
• internal/generator/e2e_operation_body_naming_test.go: generates a two-upload client, compiles it, and runs it against a test server, constructing UploadUserAvatarBody and UploadWorkflowIconBody and taking *UploadUserAvatarResponse and *UploadWorkflowIconResponse back.

Both fail on canary with undefined: UploadWorkflowIconBody.

Blast radius

Regenerating every spec in testdata/ is byte identical, since those name their bodies as components. Only specs that repeat an inline shape see names move, which is the point.