ci: gate native smoke by changed paths

[luoye520ww]

Problem

Native packaging is expensive, but skipping it for runtime or packaging changes can let Linux/Windows/macOS regressions reach main. Conversely, documentation-only changes should not trigger a full package smoke run.

Scope

This PR adds a pure changed-path gate. It does not modify GitHub workflow YAML or execute any smoke command.

Changes

• Classify changed paths as native-smoke-required or native-smoke-skipped-with-reason.
• Require smoke for main/preload, electron-builder configuration, packaging scripts, icons, Kun runtime, and dependency/extension package changes.
• Normalize Windows separators and duplicate paths.
• Force smoke for workflow_dispatch or an explicit force flag.
• Return matched rule IDs and human-readable reasons for CI diagnostics.

Safety

• Unknown and documentation-only paths produce an explicit skip reason, never a silent pass.
• The gate is deterministic and side-effect free.
• It does not read repository contents, call GitHub, or run shell commands.

Typecheck

npm.cmd run typecheck

Passed.

Tests

node --test scripts/native-smoke-path-gate.test.cjs
npm.cmd run lint
npm.cmd run build
git diff --check

Passed: 6 path-gate tests; root typecheck, lint, and build passed; diff check passed.

Review performed

• Path matching and normalization
• Manual dispatch/force behavior
• CI diagnostic output
• Cross-platform path handling
• Test quality and PR scope

Non-goals

• Editing GitHub Actions workflows
• Computing Git diffs
• Running or uploading native package artifacts
• Packaging smoke implementation

Follow-ups

H2 workflow integration can consume this result to set native-smoke-required and skip only low-risk changes with the returned reason.

[luoye520ww]

This work is consolidated into #941, which contains the related CI diagnostics and packaged smoke fix as one tested PR. Closing this duplicate to avoid parallel review and PR noise.