fix(tests/postgres): implement uuid-based isolation and reliable resource cleanup (#2377)

…atements

## Description

This PR resolves integration test resource leaks and memory exhaustion
by implementing per-test isolation and reliable teardown logic.

**Files Updated:**

- **tests/common.go**: Refactored CleanupPostgresTables to target
specific uniqueID resources.
- **tests/alloydbpg/alloydb_pg_integration_test.go**: Integrated
t.Cleanup and unique ID logging.

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🛠️ Fixes #<2463>

tests/cloudsqlpg/cloud_sql_pg_integration_test.go

@@ -114,13 +114,18 @@ func TestCloudSQLPgSimpleToolEndpoints(t *testing.T) {
 		t.Fatalf("unable to create Cloud SQL connection pool: %s", err)
 	}
 
-	// cleanup test environment
-	tests.CleanupPostgresTables(t, ctx, pool)
+	// Generate a unique ID
+	uniqueID := strings.ReplaceAll(uuid.New().String(), "-", "")
 
-	// create table name with UUID
-	tableNameParam := "param_table_" + strings.ReplaceAll(uuid.New().String(), "-", "")
-	tableNameAuth := "auth_table_" + strings.ReplaceAll(uuid.New().String(), "-", "")
-	tableNameTemplateParam := "template_param_table_" + strings.ReplaceAll(uuid.New().String(), "-", "")
+	// This will execute after all tool tests complete (success, fail, or t.Fatal)
+	t.Cleanup(func() {
+		tests.CleanupPostgresTables(t, context.Background(), pool, uniqueID)
+	})
+
+	//Create table names using the UUID
+	tableNameParam := "param_table_" + uniqueID
+	tableNameAuth := "auth_table_" + uniqueID
+	tableNameTemplateParam := "template_param_table_" + uniqueID
 
 	// set up data for param tool
 	createParamTableStmt, insertParamTableStmt, paramToolStmt, idParamToolStmt, nameParamToolStmt, arrayToolStmt, paramTestParams := tests.GetPostgresSQLParamToolInfo(tableNameParam)