rsnix: memory management — free-list heap, bitmap pages, paging adoption

- uefi.rs: full EfiMemoryType constants (0-14) + memory_type_name(); fix
  MEMORY_TYPE_LOADER_DATA from 6 to 2 per the UEFI spec
- memory.rs: replace the bump allocator with a first-fit free-list heap
  (splitting, coalescing, 8-byte back-pointer for alignment-safe free);
  add a bitmap physical page allocator (heap region reserved, page-0
  guard, aligned runs); grow the heap from the page allocator on demand
- paging.rs: identity page-table helpers — adopt_tables() rebuilds the
  firmware map into our own tables (OVMF maps its tables read-only, so
  the firmware tree can't be modified in place) and switches CR3;
  map_page/unmap_page/is_mapped with 2 MB/1 GB large-page splitting
- main.rs: boot self-tests for heap, pages, and paging

1 files changed, 32 insertions, 0 deletions

diff --git a/rsdos/src/main.rs b/rsdos/src/main.rs
index 543556b..1169785 100644
--- a/rsdos/src/main.rs
+++ b/rsdos/src/main.rs
@@ -106,6 +106,38 @@ pub extern "efiapi" fn efi_main(image_handle: Handle, system_table: *mut SystemT
 
     dump_memory_summary();
 
+    if rsnix::memory::self_test() {
+        rsnix::serial_println!("heap: self-test OK (alloc/free/coalesce)");
+    } else {
+        rsnix::serial_println!("heap: self-test FAILED");
+    }
+
+    if rsnix::memory::init_page_allocator() {
+        rsnix::serial_println!("pages: bitmap allocator ready");
+    } else {
+        rsnix::serial_println!("pages: init FAILED");
+    }
+    if rsnix::memory::page_self_test() {
+        rsnix::serial_println!("pages: self-test OK (alloc/free/runs)");
+    } else {
+        rsnix::serial_println!("pages: self-test FAILED");
+    }
+
+    if rsnix::paging::adopt_tables() {
+        rsnix::serial_println!(
+            "pg: adopted own page tables (cr3={:#x})",
+            rsnix::paging::cr3()
+        );
+    } else {
+        rsnix::serial_println!("pg: adopt_tables FAILED");
+    }
+
+    if rsnix::paging::self_test() {
+        rsnix::serial_println!("pg: self-test OK (map/unmap/split)");
+    } else {
+        rsnix::serial_println!("pg: self-test FAILED");
+    }
+
     rsnix::serial_println!("boot: entering shell");
     shell::run();
 }