chore: update opapi deps

[sea-grass]

This dependency update PR replaces tsup with tsdown and updates openapi-typescript. The opapi version is bumped a patch to 1.0.1.

The tsdown upgrade catches and fixes some issues with exported types.

The openapi-typescript upgrade comes with some improvements to generator types to make them both more accurate and lax.

[greptile-apps]

Greptile Summary

This PR updates opapi's build and OpenAPI type-generation stack. The main changes are:

• Bumps @bpinternal/opapi to 1.0.1.
• Replaces tsup with tsdown for package builds.
• Upgrades openapi-typescript to v7.
• Updates the OpenAPI TypeScript generator to use AST output.
• Adjusts generated helper types for operation and handler inference.

Confidence Score: 4/5

The package build path needs fixes before merging.

• The new build command no longer spells out the published output files.
• The new build toolchain can fail on Node versions that the package does not currently reject.
• The generator and helper-type changes look aligned with the updated OpenAPI generator path.

opapi/package.json

Important Files Changed

Filename	Overview
opapi/package.json	Updates the package version, build command, and key build/type-generation dependencies; the new build command and Node requirement need follow-up.
opapi/pnpm-lock.yaml	Refreshes the dependency graph for tsdown and openapi-typescript v7, including new native build-tool packages.
opapi/src/generators/openapi-typescript.ts	Migrates OpenAPI type generation to the async AST-based openapi-typescript v7 API.
opapi/src/generators/types.ts	Relaxes generated operation/helper types and filters path-level non-handler keys.
opapi/src/opapi.ts	Converts several imports and exports to type-only form for cleaner emitted output.

_{Reviews (1): Last reviewed commit: "chore: update opapi deps" | Re-trigger Greptile}

[greptile-apps]

Build Output Contract Can Drift

The old command explicitly built src/index.ts with CJS, ESM, declarations, and a clean output, but bare tsdown now relies on default discovery. If tsdown does not emit the same dist/index.js, dist/index.mjs, and dist/index.d.ts files referenced by this package, the release can build with missing or renamed artifacts and consumers will fail to resolve the package.

Note: If this suggestion doesn't match your team's coding style, reply to this and let me know. I'll remember it for next time!

[greptile-apps]

Build Tool Requires Newer Node

The new tsdown toolchain pulls in rolldown native bindings with a Node floor of ^20.19.0 || >=22.12.0, but the package does not declare that runtime requirement. CI or local builds on older supported Node versions can install dependencies and then fail when pnpm build runs.