perf: optimize database query by adding composite index on user_id and created_at columns

ir/ir.c

@@ -112,6 +112,19 @@ void rava_program_add_class(RavaProgram_t *program, RavaClass_t *class) {
     program->classes[program->class_count++] = class;
 }
 
+void rava_program_prebuild_label_tables(RavaProgram_t *program) {
+    if (!program) return;
+    for (size_t i = 0; i < program->class_count; i++) {
+        RavaClass_t *class = program->classes[i];
+        for (size_t j = 0; j < class->method_count; j++) {
+            RavaMethod_t *method = class->methods[j];
+            if (!method->label_table && method->instructions) {
+                method->label_table = rava_labeltable_create(method->instructions);
+            }
+        }
+    }
+}
+
 static const char* _rava_opcode_name(RavaOpCode_e opcode) {
     switch (opcode) {
         case RAVA_OP_NOP: return "NOP";