feat(waybar+sway): bluetooth module + unify wifi/bt toggle paths

- systemd-units/system/bt.txt: new file pairing the meta/bt.txt group;
  enables bluetooth.service via 'just unit-apply'
- waybar: add the built-in bluetooth module; on-click runs the same
  bt-toggle.sh that XF86Bluetooth has always invoked. Status colors:
  blue when adapter is up, green when a device is connected, gray off
- sway: XF86WLAN now runs wifi-toggle.sh (iwd D-Bus) instead of
  'rfkill toggle wifi'. The latter required rfkill group membership
  (user is in wheel only), and aligning on the busctl path means the
  keybind and the waybar click drive the same code

XF86RFKill (panic-disable all radios) keeps using 'rfkill toggle all' —
that scope is genuinely rfkill-shaped.

2 files changed, 27 insertions, 0 deletions

diff --git a/dot_config/waybar/config.jsonc b/dot_config/waybar/config.jsonc
index 275d795..47d6b64 100644
--- a/dot_config/waybar/config.jsonc
+++ b/dot_config/waybar/config.jsonc
@@ -14,6 +14,7 @@
     "privacy",
     "pulseaudio",
     "custom/wifi",
+    "bluetooth",
     "idle_inhibitor",
     "custom/notifications",
     "custom/thunderbird",
@@ -146,6 +147,18 @@
     "tooltip": true,
   },
 
+  "bluetooth": {
+    "format": "BT on",
+    "format-disabled": "BT off",
+    "format-off": "BT off",
+    "format-connected": "BT {device_alias}",
+    "format-connected-battery": "BT {device_alias} {device_battery_percentage}%",
+    "tooltip-format": "{controller_alias}\t{controller_address}",
+    "tooltip-format-connected": "{controller_alias}\n{num_connections} connected\n{device_enumerate}",
+    "tooltip-format-enumerate-connected": "{device_alias}\t{device_address}",
+    "on-click": "~/.config/sway/bt-toggle.sh",
+  },
+
   "privacy": {
     "icon-spacing": 4,
     "icon-size": 14,
diff --git a/dot_config/waybar/style.css b/dot_config/waybar/style.css
index 037c0e3..3072ad2 100644
--- a/dot_config/waybar/style.css
+++ b/dot_config/waybar/style.css
@@ -40,6 +40,7 @@ window#waybar {
 #memory,
 #temperature,
 #network,
+#bluetooth,
 #pulseaudio,
 #tray,
 #window,
@@ -80,6 +81,19 @@ window#waybar {
   color: #928374; /* gray */
 }
 
+#bluetooth {
+  color: #83a598; /* blue when on, no connections */
+}
+
+#bluetooth.connected {
+  color: #b8bb26; /* green when a device is connected */
+}
+
+#bluetooth.disabled,
+#bluetooth.off {
+  color: #928374; /* gray when adapter is off */
+}
+
 #battery {
   color: #fabd2f; /* yellow */
 }