feat(edgecfg): Phase 267 P0 BranchStub + emit_frag (Branch→MIR)

src/mir/builder/control_flow/edgecfg/api/mod.rs

@@ -21,11 +21,13 @@ pub mod frag;
 pub mod compose;
 pub mod verify;
 pub mod emit; // Phase 266: 追加
+pub mod branch_stub; // Phase 267 P0: 追加
 
 // 公開型（安定）
 pub use exit_kind::ExitKind;
 pub use edge_stub::EdgeStub;
 pub use frag::Frag;
+pub use branch_stub::BranchStub; // Phase 267 P0: 追加
 
 // 合成関数（Phase 264: crate内のみ公開、Phase 265+でpub化）
 pub(crate) use compose::{seq, if_, loop_, cleanup};
@@ -34,5 +36,5 @@ pub(crate) use compose::{seq, if_, loop_, cleanup};
 pub use verify::verify_frag_invariants;
 pub use verify::verify_frag_invariants_strict; // Phase 266: strict 版追加
 
-// Phase 266: wires → MIR terminator 変換
-pub use emit::emit_wires;
+// Phase 267 P0: wires + branches → MIR terminator 変換
+pub use emit::{emit_wires, emit_frag};