fix(power): #60 name-agnostic system-battery scan

Replace BAT* globs with type=Battery + !scope=Device (same filter as
nomarchy-battery-notify) in charge-limit oneshot, menu gates, Waybar
power-profile self-gate, doctor, and install chassis detection. CMB0-
style names get charge-cap and laptop modules consistently.

V3 pending: confirm on non-BAT* hardware (HARDWARE-QUEUE). Close #60.

Verified: V1 (option-docs, hardware-db-modules, battery-charge-limit VM).

modules/nixos/options.nix

@@ -106,8 +106,9 @@
         example = 80;
         description = ''
           Stop charging at this percentage to extend battery lifespan,
-          where the hardware exposes a charge threshold
-          (/sys/class/power_supply/BAT*/charge_control_end_threshold).
+          where the hardware exposes charge_control_end_threshold on a
+          system battery (type=Battery under /sys/class/power_supply;
+          name-agnostic — BAT0, CMB0, …).
           null leaves charging at the firmware default. Backend-independent
           (a small systemd unit writes the sysfs knob, re-applied on AC
           state changes), so it works under PPD too; needs