Add detailed logging when safety checks fail

When the migration detects unexpected data, it now logs:
- Each server that would be deleted, with name, version, and reason
- Each server that would have status updated, with current status

This makes it easy to identify new problematic data and update
the migration accordingly if production data changes.

Example output on failure:
```
NOTICE: Servers that would be deleted:
NOTICE:   - unexpected.server/[email protected] (reason: Invalid name format)
NOTICE:   - another.server@ (reason: Empty version)
ERROR: Safety check failed: Expected to delete exactly 5 servers but would delete 7
```

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <[email protected]>

Author: tadasant

internal/database/migrations/008_clean_invalid_data.sql

@@ -12,6 +12,7 @@ DECLARE
     duplicate_count INTEGER;
     total_to_delete INTEGER;
     total_servers INTEGER;
+    r RECORD;
 BEGIN
     -- Get total server count
     SELECT COUNT(*) INTO total_servers FROM servers;
@@ -69,11 +70,42 @@ BEGIN
     -- - 5 servers to delete (1 invalid name + 4 empty versions)
     -- - 1 server status to update
     IF total_to_delete != 5 THEN
-        RAISE EXCEPTION 'Safety check failed: Expected to delete exactly 5 servers but would delete %. Aborting to prevent data loss.', total_to_delete;
+        -- Log the specific servers that would be deleted
+        RAISE NOTICE 'Servers that would be deleted:';
+        FOR r IN
+            SELECT value->>'name' as name, value->>'version' as version,
+                   CASE
+                       WHEN value->>'name' NOT SIMILAR TO '[a-zA-Z0-9][a-zA-Z0-9.-]*[a-zA-Z0-9]/[a-zA-Z0-9][a-zA-Z0-9._-]*[a-zA-Z0-9]' THEN 'Invalid name format'
+                       WHEN value->>'version' IS NULL THEN 'NULL version'
+                       WHEN value->>'version' = '' THEN 'Empty version'
+                   END as reason
+            FROM servers
+            WHERE value->>'name' NOT SIMILAR TO '[a-zA-Z0-9][a-zA-Z0-9.-]*[a-zA-Z0-9]/[a-zA-Z0-9][a-zA-Z0-9._-]*[a-zA-Z0-9]'
+               OR value->>'version' IS NULL
+               OR value->>'version' = ''
+            ORDER BY value->>'name'
+        LOOP
+            RAISE NOTICE '  - %@% (reason: %)', r.name, r.version, r.reason;
+        END LOOP;
+
+        RAISE EXCEPTION 'Safety check failed: Expected to delete exactly 5 servers but would delete %. Check the log above for details. Aborting to prevent data loss.', total_to_delete;
     END IF;
 
     IF invalid_status_count != 1 THEN
-        RAISE EXCEPTION 'Safety check failed: Expected to update exactly 1 server status but would update %. Aborting to prevent data corruption.', invalid_status_count;
+        -- Log the specific servers that would have status updated
+        RAISE NOTICE 'Servers that would have status updated:';
+        FOR r IN
+            SELECT value->>'name' as name, value->>'version' as version, value->>'status' as status
+            FROM servers
+            WHERE value->>'status' IS NOT NULL
+              AND value->>'status' != ''
+              AND value->>'status' NOT IN ('active', 'deprecated', 'deleted')
+            ORDER BY value->>'name'
+        LOOP
+            RAISE NOTICE '  - %@% (current status: %)', r.name, r.version, r.status;
+        END LOOP;
+
+        RAISE EXCEPTION 'Safety check failed: Expected to update exactly 1 server status but would update %. Check the log above for details. Aborting to prevent data corruption.', invalid_status_count;
     END IF;
 END $$;