test: remediate and stabilize auxiliary backend and frontend tests

- Standardized task log, LLM provider, and report profile tests.
- Relocated auxiliary tests into __tests__ directories for consistency.
- Updated git_service and defensive guards with minor stability fixes discovered during testing.
- Added UX integration tests for the reports list component.

backend/src/services/git_service.py

@@ -46,10 +46,21 @@ class GitService:
             backend_root = Path(__file__).parents[2]
             self.legacy_base_path = str((backend_root / "git_repos").resolve())
             self.base_path = self._resolve_base_path(base_path)
-            if not os.path.exists(self.base_path):
-                os.makedirs(self.base_path)
+            self._ensure_base_path_exists()
     # [/DEF:__init__:Function]
 
+    # [DEF:_ensure_base_path_exists:Function]
+    # @PURPOSE: Ensure the repositories root directory exists and is a directory.
+    # @PRE: self.base_path is resolved to filesystem path.
+    # @POST: self.base_path exists as directory or raises ValueError.
+    # @RETURN: None
+    def _ensure_base_path_exists(self) -> None:
+        base = Path(self.base_path)
+        if base.exists() and not base.is_dir():
+            raise ValueError(f"Git repositories base path is not a directory: {self.base_path}")
+        base.mkdir(parents=True, exist_ok=True)
+    # [/DEF:_ensure_base_path_exists:Function]
+
     # [DEF:_resolve_base_path:Function]
     # @PURPOSE: Resolve base repository directory from explicit argument or global storage settings.
     # @PRE: base_path is a string path.
@@ -167,6 +178,7 @@ class GitService:
         with belief_scope("GitService._get_repo_path"):
             if dashboard_id is None:
                 raise ValueError("dashboard_id cannot be None")
+            self._ensure_base_path_exists()
             fallback_key = repo_key if repo_key is not None else str(dashboard_id)
             normalized_key = self._normalize_repo_key(fallback_key)
             target_path = os.path.join(self.base_path, normalized_key)
@@ -214,6 +226,7 @@ class GitService:
     # @RETURN: Repo - GitPython Repo object.
     def init_repo(self, dashboard_id: int, remote_url: str, pat: str, repo_key: Optional[str] = None) -> Repo:
         with belief_scope("GitService.init_repo"):
+            self._ensure_base_path_exists()
             repo_path = self._get_repo_path(dashboard_id, repo_key=repo_key or str(dashboard_id))
             Path(repo_path).parent.mkdir(parents=True, exist_ok=True)