[Sync] replace the flat layout with the unified stow tree

Supersedes the old flat .config/ layout (last published 2026-06-28) with the
private repo's structure: one shared base plus per-host overlays.

- packages: common/ gui/ lw/ fl/ wm/ plus install.sh and bin/ tooling
  (dotsync, reconcile-hyde.sh)
- new README covering the layout, deploy order and the HyDE dependency
- current HyDE waybar rig (layouts/, cava), pi agent extensions, claude/
  config, tmux, presenterm, aichat roles
- fish: kp (keepassxc-cli + fzf picker, db path from $KP_DB) and
  bind_M_n_history (alt+1..9 recalls the nth history entry)
- drops cruft that should never have been tracked: the duplicate top-level
  .pi/ copy, btop.log, zellij config.kdl.bak, fish_variables
- .pi/agent/auth.json is gitignored; auth.json.example ships instead

Host-specific work sessions and the personal backlog stay in the private
tree. Endpoint locators in the llamacpp/whisper guides are placeholders
($SERVER, <own-domain>) — the guides themselves stay, since they are the
useful part.

gui/.config/waybar/modules/window.jsonc

@@ -0,0 +1,35 @@
+{
+    "hyprland/window": {
+        "format": "  {}",
+        "rotate": 0,
+        "separate-outputs": true,
+        "max-length": 1000,
+        "rewrite": {
+            "(.*) — Kitty": " $1",
+            "(.*)~": " $1",
+            "(.*) — Mozilla Firefox": "󰈹 $1",
+            "(.*)Mozilla Firefox": "󰈹 Firefox",
+            "(.*) — LibreWolf": "󰈹 $1",
+            "(.*)LibreWolf": "󰈹 LibreWolf",
+            "(.*) — Chromium": " $1",
+            "(.*)Chromium": " Chromium",
+            "(.*) - VSCodium": " $1",
+            "(.*)VSCodium": " VSCodium",
+            "(.*)Code - OSS": "󰨞  $1",
+            "(.*) - Visual Studio Code": "󰨞 $1",
+            "(.*)Visual Studio Code": "󰨞 Code",
+            "(.*) — Dolphin": "󰉋 $1",
+            "(.*) - Obsidian(.*)": "󰠮 $1",
+            "(.*)Ferdium": "󰭻 Ferdium",
+            "(.*)FreeTube": " FreeTube",
+            "(.*)Freetube": " FreeTube",
+            "(.*) - VLC media player": "󰕼 $1",
+            "(.*)Steam": "󰓓 Steam",
+            "(.*)Neovide": " Nvim",
+            "(.*)Gajim": "󰭹 Gajim",
+            "(.*)KeePassXC": " KeePassXC",
+            "(.*)Betterbird": " Betterbird",
+            "(.*)Spotify": "󰓇 Spotify"
+        }
+    }
+}