chore(config): update gitignore and env.example

- Add .qoder/repowiki/zh/ to .gitignore to exclude generated repowiki content
- Update CORE_GENERAL_TYPES in env.example to align with ontology.md 13-category entity taxonomy (Chinese labels)
- Add PIPELINE_SNAPSHOT_ENABLED config for extraction pipeline stage snapshot output
- Fix missing newline at end of env.example

.gitignore

@@ -43,3 +43,6 @@ cl100k_base.tiktoken
 libssl*.deb
 
 sandbox/lib/seccomp_redbear/target
+
+# Qoder repowiki generated content
+.qoder/repowiki/zh/