cli/add_from_fs(feat[output]): Add detailed reporting of existing repositories

why: Users need visibility into which repositories already exist in configuration and where they are located.
what:
- Show count and detailed list of existing repositories when found
- Display repository name, URL, config path, and file location for each existing repo
- Simplify logic by consolidating duplicate repository checking code
- Improve user experience with more informative output

Author: tony

src/vcspull/cli/add_from_fs.py

@@ -222,38 +222,30 @@ def add_from_filesystem(
         return
 
     repos_to_add: list[tuple[str, str, str]] = []
-    if not yes:
-        for name, url, key in found_repos:
-            target_section = raw_config.get(key, {})
-            if isinstance(target_section, dict) and name in target_section:
-                pass
-            else:
-                repos_to_add.append((name, url, key))
-
-        if not repos_to_add:
-            log.info(
-                "All found repositories already exist in the configuration. "
-                "Nothing to do.",
-            )
-            return
+    existing_repos: list[tuple[str, str, str]] = []  # (name, url, key)
+    
+    for name, url, key in found_repos:
+        target_section = raw_config.get(key, {})
+        if isinstance(target_section, dict) and name in target_section:
+            existing_repos.append((name, url, key))
+        else:
+            repos_to_add.append((name, url, key))
+
+    if existing_repos:
+        log.info(f"Found {len(existing_repos)} existing repositories in configuration:")
+        for name, url, key in existing_repos:
+            log.info(f"  - {name} ({url}) at {key}{name} in {config_file_path}")
+    
+    if not repos_to_add:
+        if existing_repos:
+            log.info("All found repositories already exist in the configuration. Nothing to do.")
+        return
 
+    if not yes:
         confirm = input("Add these repositories? [y/N]: ").lower()
         if confirm not in {"y", "yes"}:
             log.info("Aborted by user.")
             return
-    else:
-        for name, url, key in found_repos:
-            target_section = raw_config.get(key, {})
-            if isinstance(target_section, dict) and name in target_section:
-                log.info(f"Repository {key}{name} ({url}) already exists. Skipping.")
-            else:
-                repos_to_add.append((name, url, key))
-        if not repos_to_add:
-            log.info(
-                "All found repositories already exist in the configuration or were "
-                "skipped. Nothing to do.",
-            )
-            return
 
     changes_made = False
     for repo_name, repo_url, determined_base_key in repos_to_add: