feat: SKEL skeleton instrumentation - designed-but-unimplemented paths panic

- hypercall.c: 5 Phase 1.3 stubs -> HCALL-E01..E05 panic (no NOSYS return)
- drr_stub.c: snapshot alloc fail -> DRR-E01; new skeletons DRR-E02 root key
  seal, DRR-E03 task kill crypto erase, DRR-E04/E05 segment/system rollback,
  DRR-E06/E07 driver recovery ops dispatch
- sched.c: enable fail -> SCH-E02 panic (no silent demo skip)
- dkm/kernel_api.c: D1 hot-unload DKM-E01, D2 bare code loader DKM-E02,
  SIPI AP wake DKM-E03 skeletons
- virtio_net tx/rx stubs -> VNET-E01/E02; ath9k tx stub -> ATH-E01;
  xhci port reset -> XHC-E01; nvme MSI/MSI-X fail -> NVME-E01..E03 (no
  silent polling downgrade); e1000 MAC fallback -> E1K-E01
- pe_shim unimpl API -> PE-E01; PE ordinal import -> PE-E02
- kernel/main.c: lib sync / vscode install fail -> LNX-E01/E02
- NEW brand/brand.c (E1 boot anim BRAND-E01, E2 time egg BRAND-E02) and
  pkg/pkg.c (pacman skeleton PKG-E01..03), wired into UTSM MAKEFILE
- Deliberate design-internal fallbacks kept and documented (VMX skip,
  bzImage skip, KDE fallback, boot-module fallback, apic->PIC route)

CODE/DKM/e1000/e1000.c

@@ -735,11 +735,12 @@ int driver_init(const struct dkm_kernel_api *api,
         raw_log("[e1000] MAC from RAL/RAH\n");
     }
 
-    /* 仍为全 0 或多播位错误时使用与虚拟机配置一致的回退 MAC */
+    /* 仍为全 0 或多播位错误时——严格错误策略插桩：MAC 读不到 = 网卡
+     * 身份不可知，零降级 panic（E1K-E01），不再用硬编码 MAC 冒充。 */
     if ((mac[0]==0&&mac[1]==0&&mac[2]==0&&mac[3]==0&&mac[4]==0&&mac[5]==0) ||
         (mac[0] & 1)) {
-        mac[0]=0x52; mac[1]=0x54; mac[2]=0x00; mac[3]=0x12; mac[4]=0x34; mac[5]=0x56;
-        raw_log("[e1000] using fallback MAC 52:54:00:12:34:56\n");
+        raw_log("[e1000] MAC read failed (zero/multicast)\n");
+        g_log->panic("E1K-E01 MAC READ FAILED");
     }
 
     raw_mac("[e1000] MAC=", mac);