refactor(config): v3 경로 call-site sweep (kebab-app/kebab-eval/kebab-parse-image)

부모 경로에 .ingest 삽입(leaf 구조체 불변). src + 테스트 call-site 전부.
kebab-cli 테스트의 v2 TOML fixture 는 from_file 자동변환(T6) 경로 검증용으로 유지.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

crates/kebab-app/tests/config_invalidation.rs

@@ -63,7 +63,7 @@ fn chunking_change_reindexes_all_types() {
     let scanned = first.scanned;
 
     // Bump target_tokens — folds into every type's signature.
-    env.config.chunking.target_tokens += 100;
+    env.config.ingest.chunking.target_tokens += 100;
 
     let second = reingest(&env);
     assert_eq!(second.scanned, scanned);