stage-b (P0): stabilize entry — compiler_stageb.hako now emits Stage‑1 Program(JSON v0) directly (one-line), avoiding heavy MIR path; FlowEntry prefers v1→v0 first; noisy debug prints in pipeline with_usings gated. Quick core/stageb canaries PASS.

lang/src/compiler/entry/compiler_stageb.hako

@@ -1,7 +1,6 @@
 // Stage-B compiler entry — ParserBox → FlowEntry emit-only
 
 using lang.compiler.parser.box as ParserBox
-using lang.compiler.pipeline_v2.flow_entry as FlowEntryBox
 
 static box StageBMain {
   // Minimal Stage‑B driver: parse args/env, extract main body if wrapped in `box Main { static method main(){...} }`,
@@ -68,13 +67,11 @@ static box StageBMain {
 
     if body_src == null { body_src = src }
 
-    // 5) Parse and emit MIR(JSON v0)
+    // 5) Parse and emit Stage‑1 JSON v0 (Program)
+    // Bridge(JSON v0) が Program v0 を受け取り MIR に lowering するため、ここでは AST(JSON v0) を出力する。
+    // 既定で MIR 直出力は行わない（重い経路を避け、一行出力を保証）。
     local ast_json = p.parse_program2(body_src)
-    local prefer = 1
-    local out = FlowEntryBox.emit_v0_from_ast_with_context(ast_json, prefer, usings_json, null, externs_json)
-    if out == null || out == "" { out = FlowEntryBox.emit_v0_from_ast(ast_json, prefer) }
-    // TTL OFF: do not fallback to dummy JSON when emit fails. Empty output surfaces failure to caller.
-    print(out)
+    print(ast_json)
     return 0
   }
 }