restore: enhance error capture with detailed stderr logging and verbose pg_restore

- Capture all ERROR/FATAL/error: messages from pg_restore/psql stderr
- Include full error details in failure messages for better diagnostics
- Add --verbose flag to pg_restore for comprehensive error reporting
- Improve thread-safe logging in parallel cluster restore
- Help diagnose cluster restore failures with actual PostgreSQL error messages

internal/database/postgresql.go

@@ -371,6 +371,9 @@ func (p *PostgreSQL) BuildRestoreCommand(database, inputFile string, options Res
 		cmd = append(cmd, "--single-transaction")
 	}
 	
+	// Add verbose flag for better error reporting
+	cmd = append(cmd, "--verbose")
+	
 	// Database and input
 	cmd = append(cmd, "--dbname="+database)
 	cmd = append(cmd, inputFile)