fix(codegen): resolve in-document pointer $refs during type generation

[Patrick Kelly (pk8189)]

Problem

The v0.3.1 recursion fix (#113) handles $defs-named refs, but not a $ref that is an in-document JSON pointer. A hand-authored schema can express recursion that way — e.g. a query filter whose or/and groups reference the filter itself:

{ "$ref": "#/properties/filter/anyOf/0" }

schema_type::follow resolves a ref by its trailing path segment against the definitions map, so this became #/$defs/0 → does not exist → generate_types errored. Consumers then relaxed the whole tool's input to any.

Reproduced against such a schema:

Type generation error: Failed following JSON schema reference, `#/$defs/0` does not exist

Fix

A normalization pass — normalize::normalize_in_document_refs, run at the top of generate_types:

• Collect every $ref that points into the document body (#/…, not #/$defs/ or #/definitions/).
• Hoist each distinct target into definitions under a generated, collision-resistant name (InlineRef_<path>).
• Repoint every ref to it at #/definitions/<name> — including refs inside the hoisted target, so a self-referential filter becomes a proper named recursive type.
• Schemas already using $defs/definitions refs (and plain schemas) pass through untouched.

It runs by round-tripping the RootSchema through JSON (pointer resolution needs the standard document where #/properties/… is meaningful); schemas are one tool's input, so cost is negligible and paid once at registration.

Result

Such a filter schema now generates a recursive union instead of erroring:

export type ListRecordsInput = {
  object: string;
  filter?: …FilterUnion0Obj0 | …Obj1 | …Obj2 | null | undefined;
};
export type …InlineRefPropertiesFilterAnyOf0Obj1 = {
  or: …Obj0 | …Obj1 | …Obj2[];   // recurses
};

Tests

• normalize.rs unit tests: hoists the self-ref + rewrites the ref inside the hoisted def; leaves named-ref and plain schemas untouched.
• tests/in_document_recursive_refs.rs: a recursive in-document filter ref now generates real recursive types with object: string preserved and no any.
• Full pctx_codegen suite green, including the existing insta snapshots (round-trip is non-destructive).

🤖 Generated with Claude Code

[Elias Posen (eliasposen)]

Patrick Kelly (@pk8189) Can you update the changelog?