Remove migrate:begin/commit/rollback references, unify to migrate command

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Co-Authored-By: Claude <noreply@anthropic.com>

app/RSpade/Commands/Migrate/Maint_Migrate.php

@@ -78,7 +78,7 @@ class Maint_Migrate extends Command
         $this->info(' Development mode: Using automatic snapshot protection');
         $this->info('');
 
-        // Step 1: Create snapshot (migrate:begin logic)
+        // Step 1: Create snapshot
         $this->info('[1/4] Creating database snapshot...');
         if (!$this->create_snapshot()) {
             return 1;