docs(phase-20.33): update Gate-C(Core) status (v1→MIR interpreter), mark parity smokes done; clean up wording\nchore: remove unused bak/ (external backup kept)\nsmokes: add Gate-C v1 file/pipe opt-in canaries; env toggles documented\nrunner: include json_v1_bridge + bridge toggles (singleton/phi) wiring

src/config/env.rs

@@ -548,3 +548,9 @@ pub fn nyvm_bridge_early_phi_materialize() -> bool {
         .or_else(|| env_flag("NYASH_BRIDGE_EARLY_PHI_MATERIALIZE"))
         .unwrap_or(false)
 }
+
+pub fn nyvm_v1_downconvert() -> bool {
+    env_flag("HAKO_NYVM_V1_DOWNCONVERT")
+        .or_else(|| env_flag("NYASH_NYVM_V1_DOWNCONVERT"))
+        .unwrap_or(false)
+}