Migrate to chezmoi with per-host sway/waybar configs

- Restructure repo into chezmoi source layout (dot_ prefix)
- Add .chezmoi.toml.tmpl mapping hostname to hosttype (laptop/desktop)
- Template sway config.d fragments (outputs/inputs/binds) per host
- Template waybar config.jsonc with shared bar/module definitions
- Host-scope pulsemeeter (flow) and teams-for-linux (desktop hosts) via .chezmoiignore
- Trim install.sh package lists to configured software + config deps
- Remove stale kitty.conf.bak and untracked host fragments

dot_config/sway/config.d/binds.conf.tmpl

@@ -0,0 +1,6 @@
+{{ if eq .hosttype "laptop" -}}
+bindsym XF86MonBrightnessDown exec brightnessctl -d intel_backlight s 5%-
+bindsym XF86MonBrightnessUp exec brightnessctl -d intel_backlight s +5%
+
+bindsym --no-repeat $mod+Shift+r exec ~/.config/sway/scripts/toggle-refresh-rate.sh
+{{- end }}