rsnix v0.4.0: GUI input foundation — PS/2 mouse + scheduler message queues

Mouse (IRQ12, stream mode): ByteRing generalized for both PS/2 devices,
ISR routes data-port bytes by the controller's aux bit; mouse_init with
bounded-ACK handshake (boots without a mouse); packet decoder with
bit-3 resync, screen-relative deltas, buttons.  Exposed as /dev/mouse,
the `mouse` stream command, and `make test-mouse`.

Message queues (ADR 0003's GUI-era primitive): every task gets a static
16-slot TaskMsg ring; send/recv/recv_blocking with direct wake + tick
scan safety net for the lost-wakeup race; `msgrecv`/`send` commands,
`mouse <id>` routes real IRQ12 events into a task's queue, jobs shows
q=.  `make test-msg` + `make test-disk` regression pass.

1 files changed, 5 insertions, 0 deletions

diff --git a/rsdos/src/main.rs b/rsdos/src/main.rs
index 700dcc7..fc47c82 100644
--- a/rsdos/src/main.rs
+++ b/rsdos/src/main.rs
@@ -138,6 +138,11 @@ pub unsafe extern "efiapi" fn efi_main(image_handle: Handle, system_table: *mut
     rsnix::serial_println!("serial: COM1 115200 8N1");
     rsnix::ps2::init();
     rsnix::serial_println!("ps2: keyboard initialized");
+    if rsnix::ps2::mouse_init() {
+        rsnix::serial_println!("ps2: mouse ready (IRQ12, stream mode)");
+    } else {
+        rsnix::serial_println!("ps2: mouse not present");
+    }
     if rsnix::gdt::init() {
         rsnix::serial_println!("gdt: own GDT + TSS (IST: page-fault/double-fault)");
     } else {