`Bundle` names a path item component after the escaped JSON Pointer token (`~1users`), so its `$ref` doesn't resolve

Start in openapi/bundle.go at extractSimpleNameFromReference, which the issue identifies as returning the escaped final JSON Pointer token unchanged; trace how that name is used to create the path item component and its $ref. Reproduce with the supplied /paths/~1users example, then check that the resulting component name is valid and the reference resolves. Confirm the bundled document passes openapi spec validate and openapi spec inline.

Summary

When a path item is referenced by JSON Pointer into another OpenAPI document (./paths/users.yaml#/paths/~1users), openapi.Bundle (and openapi spec bundle) uses the last pointer token as written, ~1users, as the component name. The bundled document gets components.pathItems.~1users and $ref: '#/components/pathItems/~1users'. Per RFC 6901 that ref names the key /users, which doesn't exist, and ~1users isn't a valid component name either (OAS 3.1 Components keys must match ^[a-zA-Z0-9\.\-_]+$). The bundle fails openapi spec validate, though the input passes.

Reproduction

openapi.yaml:

openapi: 3.1.0
info: {title: t, version: "1"}
paths:
  /users:
    $ref: ./paths/users.yaml#/paths/~1users

paths/users.yaml:

openapi: 3.1.0
info: {title: users, version: "1"}
paths:
  /users:
    get:
      responses:
        "200":
          description: ok

$ openapi spec bundle openapi.yaml bundled.yaml
Processing OpenAPI document: openapi.yaml
✅ Successfully bundled all external references into components section
📄 Document written to: bundled.yaml
$ cat bundled.yaml
openapi: 3.1.0
info: {title: t, version: "1"}
paths:
  /users:
    $ref: '#/components/pathItems/~1users'
components:
  pathItems:
    ~1users:
      get:
        responses:
          "200":
            description: ok
$ openapi spec validate bundled.yaml
Validating OpenAPI document: bundled.yaml
❌ OpenAPI document is invalid - 1 errors:

1. [5:11] error validation-invalid-syntax reference.$ref is invalid: invalid reference: component name "/users" must match pattern ^[a-zA-Z0-9.\-_]+$
Validation completed in 1ms
Error: openAPI document validation failed

openapi spec inline bundled.yaml fails the same way: failed to resolve reference #/components/pathItems/~1users: not found -- key /users not found in sequencedmap.Map. A path with a parameter gives ~1users~1{id}. --naming counter gives the same name.

Expected result

A valid component name and a $ref that resolves to it, as for a whole-file ref: $ref: ./paths/users.yaml (a file holding only the path item) bundles to components.pathItems.users, and the bundle validates.

Actual result

components.pathItems.~1users and a $ref that points at /users. The command reports success.

Version

v1.26.1 (main, 9f2ba11) and v1.26.0. CLI from go install github.com/speakeasy-api/openapi/cmd/openapi@latest (v0.0.0-20261029045548-9f2ba118224c); openapi.Bundle called directly gives the same output.

Cause

extractSimpleNameFromReference (openapi/bundle.go:1288) replaces characters outside [a-zA-Z0-9_] in file names, but for a fragment returns the last pointer token unchanged: not unescaped (~1, ~0) and not sanitized.