build: use canonical generator module

[TristanSpeakEasy]

Why

openapi-generation-next has been renamed to the canonical openapi-generation repository after its history was squashed for open source publication. The CLI no longer needs to redirect the canonical module path to the temporary repository.

What changed

• Remove the openapi-generation/v2 → openapi-generation-next/v2 replace directive.
• Upgrade the canonical generator dependency from v2.930.1 to v2.932.0.
• Apply the required transitive dependency metadata from go mod tidy.
• Simplify scripts/upgrade.bash so future generator upgrades always read from and update the canonical repository/module.

Testing

• go mod tidy -diff
• go test ./internal/sdkgen/... ./internal/validation/...
• bash -n scripts/upgrade.bash
• go list -m -json github.com/speakeasy-api/openapi-generation/v2 resolves v2.932.0
• Confirmed there is no replacement for github.com/speakeasy-api/openapi-generation/v2

---

Summary by cubic

Switches the OpenAPI generator to the canonical github.com/speakeasy-api/openapi-generation/v2 and updates callers to the new version report capture API. Old behavior: the CLI used a replace to github.com/speakeasy-api/openapi-generation-next/v2 and consumed MergedVersionReport directly. New behavior: the CLI depends on the canonical module at v2.932.0 and consumes VersionReportCapture via .V1. Build behavior remains unchanged.

• Removes the replace directive mapping github.com/speakeasy-api/openapi-generation/v2 to github.com/speakeasy-api/openapi-generation-next/v2; bumps to v2.932.0 and runs go mod tidy (refreshes transitive versions).
• Simplifies scripts/upgrade.bash to always read releases from speakeasy-api/openapi-generation; drops -next logic.
• Adapts versioning.WithVersionReportCapture usage in internal/ci/run/run.go and integration/workflow_test.go to handle VersionReportCapture and read reports from .V1.

No migration required for users.

^{Written for commit 52abf6b. Summary will update on new commits.}

[cubic-dev-ai]

No issues found across 3 files

_{Re-trigger cubic}