move keyboard and mouse out of HAL into a standalone ps2.sys driver, implement usb stack with xhci controller discovery, hid keyboard/mouse, and bulk-only mass storage, add pci msi support with capability chain walking and software irq vector allocation (slots 16-23), rewrite user virtual memory as a USER_VA_REGION descriptor arena with per-process ownership tracking and guard page support, replacing the old bump allocator and top-down image region, add MmCreateUserRegion/MmDestroyAllUserRegions so process teardown reclaims all user va in one pass, allocate a pool-backed shadow framebuffer in hal_screen to fix cursor tearing and scroll corruption, reserve ap trampoline page below 1mb in uefi bootloader before boot services exit, rewrite memset/memcpy/memmove/memcmp with __stosq/__movsq intrinsics, promote driver flag literals to macros and add multi-tu STANDALONE_DRIVERS table to build.c, split rtl8139/rtl816x into header+source, rename KbReadScancode to KbReadKey, improve page fault output with MmDebugDescribeAddress and user region dump, fix %p to %016llX throughout.

code/drivers/fs/fat32/fat32_mount.c

@@ -0,0 +1,20 @@
+// fat32_mount.c - filesystem vtable/mount wiring.
+#include "fat32.h"
+
+void Fat32InitVtable(IO_FILESYSTEM* fs, FAT32_VOL* vol) {
+    memset(fs, 0, sizeof(*fs));
+    fs->Open       = Fat32Open;
+    fs->Read       = Fat32Read;
+    fs->Write      = Fat32Write;
+    fs->ReadAsync  = Fat32ReadAsync;
+    fs->WriteAsync = Fat32WriteAsync;
+    fs->Create     = Fat32Create;
+    fs->Delete     = Fat32Delete;
+    fs->Truncate   = Fat32Truncate;
+    fs->GetSize    = Fat32GetSize;
+    fs->Close      = Fat32Close;
+    fs->DriverCtx  = vol;
+    fs->OpenDir    = Fat32OpenDir;
+    fs->ReadDir    = Fat32ReadDir;
+    fs->CloseDir   = Fat32CloseDir;
+}