feat(run): add interactive project selection

[codeboyzhou]

Summary

• add an interactive Maven project selector for jup run mvn that works from any directory
• rank configured projects with a 14-day time-decaying recent-use score
• persist usage state safely with atomic writes and cross-process locking
• preserve the existing current-directory behavior for non-interactive environments
• remove project usage state during jup uninit
• document the new workflow in English and Simplified Chinese

Why

Developers currently need to navigate to a configured project before running its Maven build. The selector makes previously initialized projects immediately accessible from any terminal location and keeps commonly used projects at the top.

Windows arrow-key fix

The first selector implementation wrapped os.Stdin as a generic reader. On Windows this bypassed the terminal library's console-event reader, so Enter worked but arrow keys did not. Real terminal sessions now use the library's platform-native stdin/stdout, while tests retain injectable streams.

Validation

• gofmt -l .
• go vet ./...
• go tool -modfile=golangci-lint.mod golangci-lint run
• go test ./...
• go tool -modfile=govulncheck.mod govulncheck ./...
• go run build.go verify