docs/tools: Gitea token home & PR harness 검증 도구 개선

- docs/GITEA_TOKEN_HOME.md: 토큰 홈 설정 문서 업데이트
- docs/GITEA_TOKEN_HOME_RUNBOOK.md: 런북 보완
- docs/GITEA_VARIABLES_FAILURE_ANALYSIS.md: 실패 분석 문서 수정
- docs/GITEA_VARIABLES_RUNBOOK.md: 변수 런북 수정
- tools/validate_gitea_pr_harness_v1.py: PR 하네스 검증 스크립트 개선
- tools/validate_gitea_token_home_v1.py: 토큰 홈 검증 스크립트 개선

docs/GITEA_TOKEN_HOME_RUNBOOK.md

@@ -1,8 +1,8 @@
-# GITEA_TOKEN_HOME Runbook
+# GITEA_TOKEN_TAXBAIK Runbook
 
 ## 1. Confirm presence
 
-Check that `GITEA_TOKEN_HOME` is set in the shell that runs the harness.
+Check that `GITEA_TOKEN_TAXBAIK` is set in the shell that runs the harness.
 
 ## 2. Validate read-only access
 
@@ -30,7 +30,7 @@ Expected:
 
 ## 4. If it fails
 
-- `GITEA_TOKEN_HOME missing or empty`: environment is not configured
+- `GITEA_TOKEN_TAXBAIK missing or empty`: environment is not configured
 - `401 Unauthorized`: token is wrong or lacks repo scope
 - `404 Not Found`: repo or workflow path mismatch
 - `latest_run_missing`: dispatch accepted, but run listing lagged behind