feat(panic): FUCK [panic] mode=strict|fallback + realtest image variant

- UTSM panic_full returns in fallback mode (logs [PANIC:FALLBACK] + code + hit
  count); panic_halt keeps always-halt sites (CPU exception, VMM-E11 LA57,
  VMM-E15 DSK jump, UTSM-E42 test hook). Call sites given safe continuations.
- Mode passed to DSK/FirstInit/login/desktop via DSK_BOOT_FLAG_PANIC_FALLBACK;
  DKM kernel_api.panic / kern.log.panic return to driver; ext4 fatal aborts the
  op via setjmp/longjmp and DSK falls back to FAT32 ESP.
- build.ps1/Makefile: dev=strict, release=fallback, new realtest (release
  options + strict); default -Variant all; serialized iso packing under -j.
- Fix '*/' inside comments (dkm.h, kernel_api.h, bus.c) that broke the build.
- Includes pending work: dkm_bus service bus, mt7920/wlan drivers, desktop
  files/startmenu/prank, pe-tools, diskinfo, docs.

Co-authored-by: Cursor <cursoragent@cursor.com>

CODE/UTSM/dkm/boot_modules.c

@@ -414,7 +414,9 @@ int dkm_load_elf_rel(const void *address, u64 size, const struct dkm_symbol_scan
     handle.flags = desc->flags;
 
     dkm_log_set_driver(desc->name);           /* D4: 驱动自己的颜色 */
+    dkm_bus_set_current_provider(&handle);    /* D6: 总线 provider 上下文 */
     int result = init(dkm_get_kernel_api(), &handle);
+    dkm_bus_set_current_provider(0);
     dkm_log_set_driver(0);
     handle.init_status = result;
     if (result != 0) {