v0.3.0: Headless mode, crash fixes, unified versions

What changed

Both binaries now share the same version (0.3.0) — treemap_mvp was
0.1.0 and treemap-disk-analyzer was 0.2.3.

treemap-disk-analyzer (01_more)

• New --headless / --scan-only mode: prints a size-sorted summary to
  stdout, so the tool works on servers, containers and CI without an
  X server. On Linux without DISPLAY/WAYLAND_DISPLAY it falls back
  to headless automatically instead of panicking in XOpenDisplay().
• Fixed a crash on multi-byte filenames (e.g. CJK): label truncation cut
  on byte instead of char boundaries.
• Fixed a Broken-pipe panic when piping headless output into head.
• Removed the unused rayon dependency; unified the scan/merge helper
  shared by headless and GUI paths.
• Tests: 7 unit + 2 integration tests green; fmt clean;
  clippy --all-targets warning-free.

treemap_mvp (00_mvp)

• Frozen as reference implementation; no feature work planned
  (see plan/20260918_02_review/plan.md). Clippy lint fixed.

CI

• New smoke job on Ubuntu: fmt, clippy (-D warnings), tests,
  headless smoke and GUI smoke under xvfb-run.

Assets

Built automatically by .github/workflows/build.yml on tag push:

• treemap_mvp-linux, treemap_mvp-windows.exe
• treemap-disk-analyzer-linux, treemap-disk-analyzer-windows.exe

Notes

• Linux GUI needs X libraries and, without a display, xvfb
  (apt-get install -y xvfb libxkbcommon0 libxi6 libx11-6 libgl1 libasound2t64).
• notify stays at 6.1; the upgrade to 8.x is planned as a separate
  step. No new Rust dependencies were introduced in this release.

inotify watching message

• validated that watching works on a small directory tree (like ~/.cache)

chatgpt reviews

• removed parallel layout again

first

• scans drive
• displays treemap, updates live
• inotify triggers rebuild of diagram / shown with animation