Keyboard lights, TLB shootdowns, battery in sysfs, /proc/pid/maps

Caps, Num and Scroll Lock now light their LEDs on PS/2 and USB keyboards,
share one state between keyboards, and stop toggling on key repeat. X sets
them through evdev writes while it holds the keyboard.

Unmapping memory in a process with threads on other CPUs now flushes their
TLBs with an IPI. Without it a freed page stayed reachable through stale
translations, which corrupted Epiphany's heap on SMP.

ACPI batteries and AC adapters appear under /sys/class/power_supply.
/proc/<pid>/maps lists file mappings, and a process killed by a fault
names the file and offset it died in. r8169 gets a 256-entry RX ring.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01S1giNvrHTrPMPw7V6x1kQ4

include/core/proc.h

@@ -48,6 +48,7 @@ struct mm {
   uint64 mmap_next;            // next free mmap VA (bump allocator, see sys_mmap)
   pml4e_t *pgdir;
   struct vma vma[NVMA];        // VMA tracking for mmap
+  struct mapname *names;       // which file each span came from; mapname.c
 };
 
 // The descriptor table, and FD_CLOEXEC beside it.