- Add build.ps1: one-shot PowerShell build with version from git tag
- winamp_path config is now optional; roadamp works with any running
  Winamp instance regardless of install location (FindWindow does the
  discovery). Path is only needed if roadamp should launch Winamp itself.
- Remove hardcoded C:\Program Files\Winamp default

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

- Go HTTP server with Winamp IPC via WM_USER/WM_COMMAND
- internal/winamp: TWinampControl port (play/pause/stop/seek/volume/title/playlist)
- internal/killist: persistent skip-list (port of Delphi KillFile feature)
- internal/resume: JSON-based resume state (port of Delphi resume.dat)
- internal/server: HTTP API + background killist checker + resume restore
- web/static: mobile-first touch UI (dark theme, progress bar, seek buttons)
- config.yaml.example for winamp path / port / file paths

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>