Language: raw asm { ... } blocks

raw asm {
        LDA #\$42
        STA \$00
    }

Unlike regular \`asm\`, \`raw asm\` does not perform \`{var}\`
substitution — the body is passed to the inline parser verbatim.
Useful for writing completely unmanaged bytes that don't rely on
the analyzer's variable allocations, e.g. mapper init snippets.

Implementation:
- Parser: \`KwRaw\` followed by \`KwAsm\` emits
  \`Statement::RawAsm(body, span)\`.
- IR lowering: prepends a \`\\0RAW\\0\` marker to the body when
  emitting \`IrOp::InlineAsm\` so the codegen can distinguish raw
  from regular without adding a second op variant.
- IR codegen: strips the marker and skips substitution when present.
- AST codegen: same, handling \`Statement::RawAsm\` directly.

https://claude.ai/code/session_01W6eQFStA66EuMKHUFo2rx3

tests/integration_test.rs

@@ -322,6 +322,26 @@ fn program_with_enums() {
     rom::validate_ines(&rom_data).expect("should be valid iNES");
 }
 
+#[test]
+fn program_with_raw_asm_block() {
+    // `raw asm` bypasses `{var}` substitution so the body is passed
+    // to the inline parser unchanged.
+    let source = r#"
+        game "RawAsm" { mapper: NROM }
+        var x: u8 = 0
+        on frame {
+            raw asm {
+                LDA #$42
+                STA $00
+            }
+            wait_frame
+        }
+        start Main
+    "#;
+    let rom_data = compile(source);
+    rom::validate_ines(&rom_data).expect("should be valid iNES");
+}
+
 #[test]
 fn program_with_inline_asm_variable_substitution() {
     let source = r#"