Support Vite-style ?raw raw-text imports in CLI builds

[joostfarla]

Generic follow-up to developer-overheid-nl/don-checker#66 (which fixes developer-overheid-nl/don-checker#55): consumer apps import example fixtures as raw text via Vite's ?raw suffix — YAML fixtures in particular, so the editor opens them in YAML mode. Vite and Vitest support the suffix natively, but the build-cli CLI bundle (rolldown) and tsc don't. This makes both work out of the box, so consumers need no local tsdown config or ambient module declaration.

Changes

• bin/build-cli.mjs — now drives the tsdown JS API with the standard CLI-build options plus a raw-imports plugin that resolves *?raw specifiers and inlines the file content as a default-exported string.

  Why the JS API instead of spawning the tsdown CLI: plugins can only reach the CLI via a config file, and tsdown resolves relative paths (entry, tsconfig discovery) against the config file's directory — a config shipped inside this package made consumer builds resolve tsconfig: ../tsconfig.json (this package's own!) and fail on Cannot resolve entry module src/cli.ts. With the API everything stays relative to the consumer's cwd.

  Contract change: build-cli <entry> [...entry] takes entries only (flags now error with a usage message instead of being forwarded), and a consumer tsdown.config.ts is never loaded — the build is fully standard.

• client.d.ts — declares *?raw modules as strings, so tsc accepts the imports. Consumers upgrading should remove any local equivalent declaration (a duplicate would conflict).

• README + changeset (minor).

Verification

• pnpm lint clean, pnpm test run passes (131 tests), pnpm build succeeds.
• don-checker (has ?raw YAML/JSON imports): built with this build-cli after removing its local tsdown.config.ts shim — correct consumer tsconfig.json picked up, bundle validates both the YAML publiccode example and the JSON ADR example with 0 diagnostics. tsc -b also passes against the new client.d.ts with the local *?raw declaration removed.
• ogc-checker (no ?raw imports): builds unchanged and its CLI validates the JSON-FG feature example clean — no regression for consumers not using the feature.

After this lands in a release, don-checker can drop its tsdown.config.ts and src/vite-env.d.ts shims when bumping the dependency.