[Sync] adopt unified stow layout from the private repo

Mirrors the private dots tree at 900bdda: one shared base plus per-host
overlays, replacing the old flat .config/ layout (last synced 2026-06-28).

- packages: common/ gui/ wm/ lw/ fl/ + install.sh and bin/ tooling (dotsync,
  reconcile-hyde.sh)
- new README (layout, deploy order, HyDE dependency), plus ToDo.md and
  HYDE-UPDATE.md
- current HyDE waybar rig (layouts/, cava), pi agent extensions, claude/
  config, tmux, presenterm, aichat roles
- drops stale duplicates and generated cruft that should never have been
  tracked: the second top-level .pi/ copy, btop.log, zellij config.kdl.bak,
  fish_variables, nvim codecompanion.lua
- .pi/agent/auth.json is gitignored now; auth.json.example ships instead
- fl/ and wm/ hypr themes/ stay untracked (HyDE-generated per machine, per
  the root .gitignore)

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"
+        }
+    }
+}