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/banner/presets/minimal.json

@@ -0,0 +1,34 @@
+{
+  "name": "minimal",
+  "title": {
+    "uk": "Мінімальний: один рядок",
+    "en": "Minimal: one line"
+  },
+  "local": false,
+  "vars": {},
+  "fields": [
+    {
+      "x": 0,
+      "y": 0,
+      "width": 70,
+      "align": "left",
+      "text": "{hostname} · {ip} · [[працює|up]] {uptime} · {load}",
+      "style": "a"
+    }
+  ],
+  "widgets_position": "below",
+  "widgets": [],
+  "styles": {
+    "a": {
+      "fg": "bright_cyan",
+      "bg": null,
+      "bold": true
+    }
+  },
+  "lines": [],
+  "style_map": [],
+  "canvas": {
+    "width": 70,
+    "height": 1
+  }
+}