feat: FS-E strict filesystem mode - ext4 rw driver, FAT32 big-disk fix, forced re-login

- CODE/dsk/ext4.c: minimal full ext4 read/write (GPT probe, feature gate,
  extent depth 0/1 rw, block/inode alloc-free, dir insert, write-verify);
  boot selftest PASS on p2. Unsupported features panic (FS-E2x), zero fallback.
- DSK fat32 write: on-demand FAT entry RMW + chunked free-cluster scan
  (fixes "no free clusters" on 5.3G ESP); rec_len shrink offset (+4) and
  chunk alignment fixes. USER.CONF write-verify ok, firstInit flip ok.
- First-boot: wizard -> persist -> forced login (FS-E06 if skipped/failed)
  -> desktop. login.elf loaded via system/user/use fallback.
- FirstInit network page: Connect now panics NET-E01 (no wlan stack);
  Save (config only) is the only path forward.
- FirstInit/DSK fatal: ohMyLogo lotus fatal screen (NET-E01 / FS-E series).
- Boot screen: Logo.png image removed, "DESHAB P01" text centered only;
  dcp/xj logos regenerated from TEXTURES/.
- run_qemu.bat: main GPT image on SATA ide.0 (AHCI provider must see ext4).

CODE/UTSM/test/utsm_selftest.c

@@ -1,6 +1,8 @@
 #include <utsm/utsm.h>
 #include <utsm/pckc.h>
 #include <utsm/crypto.h>
+#include <utsm/dma.h>
+#include <utsm/dkm.h>
 #include <utsm/log.h>
 #include <utsm/segment.h>
 #include <utsm/arena.h>
@@ -190,6 +192,38 @@ int utsm_selftest_run(void) {
         log_info("[UTSM] selftest unsealed segment ok (plain storage)");
     }
 
+    /* ==== D3: 按名导出表（kapi）——按名取服务并调用 ==== */
+    {
+        const dkm_kernel_api *api = dkm_get_kernel_api();
+        if (!api->kapi || api->kapi->magic != DKM_KAPI_MAGIC) {
+            log_error("[UTSM] selftest kapi table missing");
+            return UTSM_ERR_INVALID;
+        }
+        void *fn = 0;
+        if (api->kapi->lookup("log.info", &fn) != 0) {
+            log_error("[UTSM] selftest kapi lookup log.info failed");
+            return UTSM_ERR_INVALID;
+        }
+        void (*klog)(const char *) = (void (*)(const char *))fn;
+        klog("[UTSM] selftest kapi: log.info via export table");
+        if (api->kapi->lookup("dma.alloc_pages", &fn) != 0) {
+            log_error("[UTSM] selftest kapi lookup dma failed");
+            return UTSM_ERR_INVALID;
+        }
+        int (*kalloc)(u64, u64, u64, dkm_dma_buffer *) = (int (*)(u64, u64, u64, dkm_dma_buffer *))fn;
+        dkm_dma_buffer kbuf;
+        if (kalloc(1, 4096, 0xFFFFFFFFULL, &kbuf) != 0 || !kbuf.virt) {
+            log_error("[UTSM] selftest kapi dma alloc failed");
+            return UTSM_ERR_INVALID;
+        }
+        if (api->kapi->lookup("no.such.service", &fn) == 0) {
+            log_error("[UTSM] selftest kapi negative lookup failed");
+            return UTSM_ERR_INVALID;
+        }
+        log_hex64("[UTSM] selftest kapi entries=", api->kapi->count);
+        log_info("[UTSM] selftest kapi ok");
+    }
+
     /* ==== SCHED-1: O(1) runqueue 语义（合成 TCB，协作式，无 tick） ==== */
     /* ==== SCHED-1 + SCHED-2: runqueue / block-wake（tick 竞态保护） ==== */
     {