refactor: archive GUI clients; keep minimal TUI with hooks/API

Move Qt/Tauri/full Web SPA under archive/, ship hermit as CLI/TUI plus
libcstcore and cst-webui/1 HTTP+SSE (turn lifecycle hooks, capabilities).

Co-authored-by: Cursor <cursoragent@cursor.com>

archive/qt-app/icons/help-hint.svg

@@ -0,0 +1,9 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24" width="24" height="24">
+  <defs id="defs3051">
+    <style type="text/css" id="current-color-scheme">.ColorScheme-Text { color: #fcfcfc; } </style>
+  </defs>
+  <g transform="translate(1,1)">
+    <path style="fill:currentColor;fill-opacity:1;stroke:none" d="M 11 3 C 6.568 3 3 6.568 3 11 C 3 15.432 6.568 19 11 19 C 15.432 19 19 15.432 19 11 C 19 6.568 15.432 3 11 3 z M 11 4 C 14.878 4 18 7.122 18 11 C 18 14.878 14.878 18 11 18 C 7.122 18 4 14.878 4 11 C 4 7.122 7.122 4 11 4 z M 10 6 L 10 8 L 12 8 L 12 6 L 10 6 z M 10 9 L 10 16 L 12 16 L 12 9 L 10 9 z " class="ColorScheme-Text"/>
+  </g>
+</svg>