chore: import upstream snapshot with attribution

backend/tests/manual/setup-large-table-extras.sql

@@ -0,0 +1,34 @@
+-- Add indexes
+CREATE INDEX IF NOT EXISTS idx_large_table_user_id ON large_table(user_id);
+CREATE INDEX IF NOT EXISTS idx_large_table_created_at ON large_table(created_at);
+CREATE INDEX IF NOT EXISTS idx_large_table_status ON large_table(status);
+
+-- Create trigger function for updating updated_at timestamp
+CREATE OR REPLACE FUNCTION update_updated_at_column()
+RETURNS TRIGGER AS $$
+BEGIN
+    NEW.updated_at = CURRENT_TIMESTAMP;
+    RETURN NEW;
+END;
+$$ LANGUAGE plpgsql;
+
+-- Create trigger to automatically update updated_at
+DROP TRIGGER IF EXISTS update_large_table_updated_at ON large_table;
+CREATE TRIGGER update_large_table_updated_at 
+    BEFORE UPDATE ON large_table
+    FOR EACH ROW
+    EXECUTE FUNCTION update_updated_at_column();
+
+-- Enable Row Level Security
+ALTER TABLE large_table ENABLE ROW LEVEL SECURITY;
+
+-- Create RLS policies
+DROP POLICY IF EXISTS "Enable read access for all users" ON large_table;
+CREATE POLICY "Enable read access for all users" 
+    ON large_table 
+    FOR SELECT 
+    USING (true);
+
+-- Grant permissions
+GRANT ALL ON large_table TO anon;
+GRANT ALL ON large_table TO authenticated;