[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/kitty/kitty.conf

@@ -0,0 +1,21 @@
+include theme.conf
+
+font_size 12.0
+font_family      CaskaydiaCove Nerd Font Mono
+bold_font        auto
+italic_font      auto
+bold_italic_font auto
+window_padding_width 25
+enable_audio_bell no
+cursor_trail 1
+cursor_blink_interval 0.4 ease-in-out
+
+tab_bar_style       powerline
+tab_powerline_style slanted
+
+confirm_os_window_close 0
+#background_opacity 0.60
+#hide_window_decorations yes
+
+# Per-host overrides (font_size, padding, opacity…) — included last so it wins.
+include host.conf