feat(joinir): Phase 213-2 Step 2-2 & 2-3 Data structure extensions

Extended PatternPipelineContext and CarrierUpdateInfo for Pattern 3 AST-based generalization.

Changes:
1. PatternPipelineContext:
   - Added loop_condition: Option<ASTNode>
   - Added loop_body: Option<Vec<ASTNode>>
   - Added loop_update_summary: Option<LoopUpdateSummary>
   - Updated build_pattern_context() for Pattern 3

2. CarrierUpdateInfo:
   - Added then_expr: Option<ASTNode>
   - Added else_expr: Option<ASTNode>
   - Updated analyze_loop_updates() with None defaults

Status: Phase 213-2 Steps 2-2 & 2-3 complete
Next: Create Pattern3IfAnalyzer to extract if statement and populate update summary

tools/exe_first_smoke.sh

@@ -28,8 +28,9 @@ fi
 echo "[4/4] Executing via bridge (pipe) to verify semantics ..."
 # Keep core minimal and deterministic
 export NYASH_DISABLE_PLUGINS=1
+BIN=${NYASH_BIN:-./target/release/hakorune}
 set +e
-timeout -s KILL 60s bash -c 'cat dist/nyash_compiler/sample.json | ./target/release/nyash --ny-parser-pipe --backend vm >/dev/null'
+timeout -s KILL 60s bash -c "cat dist/nyash_compiler/sample.json | ${BIN} --ny-parser-pipe --backend vm >/dev/null"
 RC=$?
 set -e
 if [[ "$RC" -ne 7 ]]; then