Self-referencing imports (own package name) produce `UNRESOLVED_IMPORT` warnings

Describe the bug

If a bundled entry imports the package by its own name (Node's package self-referencing through exports), obuild prints UNRESOLVED_IMPORT warnings.

Here is why. obuild marks only dependencies and peerDependencies as external (src/builders/bundle.ts#L93-L101), and the package's own name isn't one of them. So Rolldown tries to resolve pkg/foo through exports, which points into dist/. obuild has just cleaned dist/, so the lookup fails and Rolldown warns before treating the import as external.

The output itself is correct, since the specifier is kept and resolves at runtime. The problem is noise: one warning block per self-import. In env-runner that's 8 blocks on every build, from src/loader.ts lazily importing env-runner/runners/<name>.

Reproduction

package.json

{
  "name": "pkg",
  "type": "module",
  "exports": { ".": "./dist/index.mjs", "./foo": "./dist/foo.mjs" },
  "devDependencies": { "obuild": "^0.4.40" }
}

build.config.mjs

import { defineBuildConfig } from "obuild/config";

export default defineBuildConfig({
  entries: [{ type: "bundle", dts: false, input: ["src/index.ts", "src/foo.ts"] }],
});

src/foo.ts

export const foo = "foo";

src/index.ts

export const load = () => import("pkg/foo").then((m) => m.foo);

$ pnpm obuild
🧻 Cleaning up ./dist
src/index.ts (1:33) [UNRESOLVED_IMPORT] Could not resolve 'pkg/foo' in src/index.ts
  ...
  ╰── Module not found, treating it as an external dependency
✅ obuild finished in 71ms

$ cat dist/index.mjs
const load = () => import("pkg/foo").then((m) => m.foo);
export { load };

$ node -e 'import("pkg").then((m) => m.load()).then(console.log)'
foo

Expected

No warning. obuild could add the package's own name to the default externals, along with dependencies and peerDependencies:

...[ctx.pkg.name, ...Object.keys(ctx.pkg.dependencies || {}), ...Object.keys(ctx.pkg.peerDependencies || {})]
  .filter(Boolean)
  .flatMap((p) => [p, new RegExp(`^${p}/`)]),

Workaround for now: rolldown: { external: [/^pkg(\/|$)/] }.

Versions

• obuild 0.4.40 (latest)
• rolldown 1.2.8
• Node.js 24.20.0

🤖 Generated with AI assistant

Start in src/builders/bundle.ts around lines 93-101, where dependencies and peerDependencies are added to the default externals. Reproduce the issue with the provided package.json, build.config.mjs, and src/index.ts using pnpm obuild; done means self-referencing imports produce no UNRESOLVED_IMPORT warning while the generated import remains external.