feat: support scoped workspace source builds

[emosheeep]

Summary

• scope Rspack source resolution to dependent workspace projects discovered by the active monorepo strategy
• support global and per-package resolvePriority without adding a separate package-selection API
• preserve native aliases, dependency conditions, user externals, loader resolvers, child compilers, and source/output fallback behavior
• rely on Rspack's module graph and watch dependencies instead of manually extending source.include
• expose the existing monorepo adapter types needed by framework integrations

Compatibility

• use dependency-specific getResolve when available
• retain a documented resolver-factory fallback for Rsbuild/Rspack 1.x, including watch dependency propagation
• add a real-version matrix covering Rsbuild 1.0.1 and 2.1.13

Tests

• add focused resolver, adapter, Rspack lifecycle, externals, alias, child-compiler, and watch tests
• add a miniature monorepo fixture covering direct and transitive source dependencies, package-level output priority, undeclared workspace packages, and external node_modules packages

pnpm install --frozen-lockfile
pnpm exec playwright install chromium
pnpm exec rstest run
pnpm lint
pnpm build

Local verification: 24/24 tests passed; Rslint reported 0 errors and 0 warnings; build, formatting, frozen lockfile, and diff checks passed.

Documentation

• document the scoped resolution model and public options in English and Chinese
• add contribution guidelines and a pull request template