Terminal: Das prompt, dprompt and dbanner (0.9.1)

- das-shell 0.1.0: the Das two-line bash prompt by default (replaces the
  PS1 of Void's skel .bashrc once), dprompt (Textual prompt builder with
  presets and live preview) and dbanner (SSH login banner editor: canvas
  tools, fields with values, widgets, das-banner service for cached ones,
  Das OS logo and tryzub pictures). Python tests in make test.
- das-server 0.3.0 depends on das-shell; the server installer mentions
  dprompt and dbanner; the desktop image includes it.
- run-qemu.sh forwards the guest's SSH to localhost:2222.
- Hardware fixes: Ventoy menu icon, boot menu titles "Das OS <version>".

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

srcpkgs/das-shell/files/share/prompt/presets/das-git.json

@@ -0,0 +1,17 @@
+{
+  "name": "das-git",
+  "title": {"uk": "Das для розробника: git, venv, фонові задачі", "en": "Das for developers: git, venv, background jobs"},
+  "frame": "das",
+  "frame_fg": "red",
+  "segments": [
+    {"type": "status"},
+    {"type": "userhost"},
+    {"type": "time"},
+    {"type": "cwd"},
+    {"type": "git"},
+    {"type": "venv"},
+    {"type": "jobs"},
+    {"type": "newline"},
+    {"type": "symbol"}
+  ]
+}