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>

scripts/package_windows_app.sh

@@ -1,5 +1,6 @@
 #!/usr/bin/env bash
-# Build and pack the Windows GUI (app/cst-agent-app.exe) from Linux.
+# ARCHIVED: Qt GUI lives under archive/qt-app; not part of default Hermit builds.
+# Build and pack the Windows GUI (archive/qt-app/cst-agent-app.exe) from Linux.
 #
 #   scripts/package_windows_app.sh            (run it from the repo root)
 #   nix-shell shell-win.nix --run scripts/package_windows_app.sh
@@ -161,7 +162,7 @@ cmake -S "$ROOT" -B "$BUILD" -G Ninja \
 # POSIX (tests/test_tools_ext.c calls mkdir with two arguments), exactly as in
 # the TUI cross build.
 cmake --build "$BUILD" -j"$(nproc)" --target cst-agent-app
-EXE="$BUILD/app/cst-agent-app.exe"
+EXE="$BUILD/archive/qt-app/cst-agent-app.exe"
 [[ -f "$EXE" ]] || { echo "no cst-agent-app.exe" >&2; exit 1; }
 
 # --- the package -----------------------------------------------------------