docs(live-power): document C3 wake-safety invariant; tidy rcorder block

clawdie_live_power is a one-shot boot script that applies the power_profile
C-state policy once (FreeBSD's power_profile is nostart and otherwise only
runs on a devd AC-line transition). Comment-only clarification — no behavior
change:

- Move the PROVIDE/REQUIRE/BEFORE/KEYWORD rcorder block to the top (convention;
  rcorder scans the whole file, so behavior is identical).
- Document scope explicitly: this selects a CPU C-state/freq profile ONLY —
  never suspend/sleep/blank/DPMS (screen-blank is the separate no-blank stack).
- Record the wake-safety invariant: both AC (0x01) and battery (0x00) branches
  are safe because rc.conf pins performance_cx_lowest AND economy_cx_lowest to
  C3, so neither can select a deeper C-state that breaks USB resume. Guard-rail
  for future editors: do not deepen on the live USB.

sh -n clean; rcorder tags intact.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

live/operator-session/clawdie-live-power

@@ -1,14 +1,22 @@
 #!/bin/sh
+# PROVIDE: clawdie_live_power
+# REQUIRE: FILESYSTEMS syslogd
+# BEFORE: LOGIN
+# KEYWORD: nojail
+#
 # Clawdie operator USB live power baseline.
 # Applies the rc.conf power_profile C-state policy once at boot. FreeBSD's
 # power_profile service is marked nostart and normally runs only when devd sees
 # an AC-line transition, so a live USB can otherwise sit at the firmware/default
 # C-state until AC is unplugged/replugged.
-
-# PROVIDE: clawdie_live_power
-# REQUIRE: FILESYSTEMS syslogd
-# BEFORE: LOGIN
-# KEYWORD: nojail
+#
+# Scope: this selects a CPU C-state/frequency profile ONLY. It never suspends,
+# sleeps, blanks the screen, or enables DPMS (screen-blank is handled separately
+# by the no-blank stack: xorg.conf.d/40-clawdie-noblank.conf + the power-manager
+# skel + clawdie-noblank-guard.sh). Both branches are wake-safe: rc.conf pins
+# performance_cx_lowest AND economy_cx_lowest to C3, so neither the AC (0x01) nor
+# battery (0x00) profile can drop into a deeper C-state that breaks the
+# USB-backed resume path. Keep both at C3 on the live USB — do not deepen.
 
 . /etc/rc.subr