Enhance command execution with improved concurrency and documentation updates. Refined the CommandTaskContext structure for better task management and clarified usage instructions for 'memtest' and 'tasktest' commands in README.md.

task.c

@@ -1,7 +1,7 @@
 /*
  * task.c – Cooperative multitasking: PCB pool, scheduler, yield/exit.
  *
- * Task 0 is the kernel/shell thread (uses the boot stack).
+ * Task 0 is the always-present kernel core thread (uses the boot stack).
  * Additional tasks are created with task_create(), which allocates a
  * stack from the PMM and sets up a fake context-switch frame so that
  * context_switch() can "return" into a trampoline that calls the real
@@ -57,7 +57,7 @@ static void wstrcpy16(CHAR16 *dst, const CHAR16 *src, UINTN max)
 
 /*
  * Initialise the scheduler: clear all PCB slots and register the
- * currently running kernel thread as task 0.
+ * currently running kernel core thread as task 0.
  */
 void task_init(BootInfo *Boot)
 {
@@ -79,7 +79,7 @@ void task_init(BootInfo *Boot)
     }
 
     /*
-     * Task 0 = the currently running kernel thread (the shell).
+     * Task 0 = the currently running kernel core thread.
      * It already has a stack (the kernel's boot stack), so we don't
      * allocate one.  Its saved_rsp will be filled in during the
      * first context_switch call in task_yield().
@@ -87,7 +87,7 @@ void task_init(BootInfo *Boot)
     tasks[0].pid      = next_pid++;
     tasks[0].state    = TASK_STATE_RUNNING;
     tasks[0].switches = 1;
-    wstrcpy16(tasks[0].name, L"kernel", TASK_NAME_LEN);
+    wstrcpy16(tasks[0].name, L"core", TASK_NAME_LEN);
 
     current_task = &tasks[0];
     task_ready   = TRUE;
@@ -329,6 +329,25 @@ UINTN task_count(void)
     return count;
 }
 
+/* ----------------------------------------------------------------
+ *  Wait for another task to finish
+ * ---------------------------------------------------------------- */
+
+void task_wait(Task *t)
+{
+    if (!task_ready || t == NULL) {
+        return;
+    }
+
+    /*
+     * Busy-wait cooperatively until the target task's PCB slot has
+     * been recycled back to FREE by task_exit().
+     */
+    while (t->state != TASK_STATE_FREE) {
+        task_yield();
+    }
+}
+
 /* ----------------------------------------------------------------
  *  Print task list  (implements the `ps` command)
  * ---------------------------------------------------------------- */