Rename sessions to _sessions, drop legacy migrations table

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

Co-Authored-By: Claude <noreply@anthropic.com>

app/RSpade/CodeQuality/Rules/PHP/DbTableUsage_CodeQualityRule.php

@@ -88,11 +88,6 @@ class DbTableUsage_CodeQualityRule extends CodeQualityRule_Abstract
                     continue;
                 }
 
-                // Skip Laravel's sessions table - managed by framework
-                if ($table_name === 'sessions') {
-                    continue;
-                }
-
                 // Skip framework internal tables (prefixed with underscore)
                 // These are low-level system tables managed directly for performance
                 if (str_starts_with($table_name, '_')) {