Add ThinkPad mic mute LED sync following XPS hardware handler pattern (#4938)

Omarchy 3.5.1 shipped hardware-specific mic mute handling for Dell XPS
(bin/omarchy-cmd-mic-mute-xps) which made the original PR #4938 approach
obsolete — that PR added a global omarchy-cmd-mic-mute that handled the
toggle inline, but upstream now owns that dispatcher.

This follows the same pattern to add ThinkPad support by extending
omarchy-hw-match to also check product_family (ThinkPad systems report
"ThinkPad T14s Gen 2a" there, not in product_name) and adding
omarchy-cmd-mic-mute-thinkpad which uses brightnessctl to sync the
platform::micmute LED, simpler than the ALSA approach needed for XPS.

Note: as more vendors are added this per-vendor dispatcher will get
unwieldy. A future refactor could move hardware LED sync into
install/config/hardware/ scripts that drop a hook or config file,
keeping omarchy-cmd-mic-mute thin and vendor-agnostic.

bin/omarchy-cmd-mic-mute

@@ -1,9 +1,11 @@
 #!/bin/bash
 
-# Toggle microphone mute. Dell XPS systems get special handling for the hardware LED.
+# Toggle microphone mute. Dell XPS and ThinkPad systems get special handling for the hardware LED.
 
 if omarchy-hw-match "XPS"; then
   omarchy-cmd-mic-mute-xps
+elif omarchy-hw-match "ThinkPad"; then
+  omarchy-cmd-mic-mute-thinkpad
 else
   omarchy-swayosd-client --input-volume mute-toggle
 fi