fix(model): disable PostgreSQL prepared statements for pooler compatibility

GORM v1.25.2 closes cached prepared statements asynchronously on any SQL
error and immediately re-Parses the same deterministic name (pgx's
stmt_<sha256>) on the same client connection. Transaction-pooling proxies
(PgBouncer >=1.21 with max_prepared_statements, Neon, Supabase) respond
with FATAL "prepared statement name is already in use" (SQLSTATE 08P01)
and drop the connection. PreferSimpleProtocol only disables pgx's
implicit prepare and never covered GORM's explicit PrepareStmt cache.

- PostgreSQL now runs with PrepareStmt disabled entirely; named prepared
  statements are fundamentally session state and cannot be made safe
  under transaction pooling. Parse/plan cost is noise for this workload.
- Upgrade gorm to v1.25.12 so MySQL/SQLite statement caches (still
  enabled) no longer churn close/re-prepare on ordinary SQL errors;
  v1.25.9+ restricts eviction to driver.ErrBadConn. Deliberately not
  v1.26+, whose LRU eviction has an open use-after-close race (#7831).
- sanitizeDBError now attaches a remediation hint on 08P01/42P05 so
  affected deployments can self-diagnose from the log line.

go.mod

@@ -58,7 +58,7 @@ require (
 	gopkg.in/yaml.v3 v3.0.1
 	gorm.io/driver/mysql v1.4.3
 	gorm.io/driver/postgres v1.5.2
-	gorm.io/gorm v1.25.2
+	gorm.io/gorm v1.25.12
 )
 
 require (

go.sum

@@ -3030,6 +3030,8 @@ gorm.io/gorm v1.23.8/go.mod h1:l2lP/RyAtc1ynaTjFksBde/O8v9oOGIApu2/xRitmZk=
 gorm.io/gorm v1.24.6/go.mod h1:L4uxeKpfBml98NYqVqwAdmV1a2nBtAec/cf3fpucW/k=
 gorm.io/gorm v1.25.2 h1:gs1o6Vsa+oVKG/a9ElL3XgyGfghFfkKA2SInQaCyMho=
 gorm.io/gorm v1.25.2/go.mod h1:L4uxeKpfBml98NYqVqwAdmV1a2nBtAec/cf3fpucW/k=
+gorm.io/gorm v1.25.12 h1:I0u8i2hWQItBq1WfE0o2+WuL9+8L21K9e2HHSTE/0f8=
+gorm.io/gorm v1.25.12/go.mod h1:xh7N7RHfYlNc5EmcI/El95gXusucDrQnHXe0+CgWcLQ=
 gotest.tools v2.2.0+incompatible/go.mod h1:DsYFclhRJ6vuDpmuTbkuFWG+y2sxOXAzmJt81HFBacw=
 gotest.tools/v3 v3.0.2/go.mod h1:3SzNCllyD9/Y+b5r9JIKQ474KzkZyqLqEfYqMsX94Bk=
 gotest.tools/v3 v3.0.3/go.mod h1:Z7Lb0S5l+klDB31fvDQX8ss/FlKDxtlFlw3Oa8Ymbl8=

model/gorm_logger.go

@@ -72,6 +72,11 @@ func sanitizeDBError(err error) error {
 	}
 	var pgErr *pgconn.PgError
 	if errors.As(err, &pgErr) {
+		// 08P01 是 PgBouncer 对同连接重名 Parse 的 FATAL,42P05 是原生 PostgreSQL 的
+		// duplicate_prepared_statement;都指向预处理语句与事务池代理不兼容。
+		if pgErr.Code == "08P01" || pgErr.Code == "42P05" {
+			return fmt.Errorf("postgres error SQLSTATE %s: prepared statement conflict with a transaction-pooling proxy (PgBouncer/Neon/Supabase); other clients sharing this database must disable prepared statements, or upgrade PgBouncer to >=1.21 with max_prepared_statements enabled", pgErr.Code)
+		}
 		return fmt.Errorf("postgres error SQLSTATE %s", pgErr.Code)
 	}
 	var chErr *proto.Exception

model/gorm_logger_test.go

@@ -35,6 +35,12 @@ func TestSanitizeDBErrorStripsDriverMessage(t *testing.T) {
 			want:   "postgres error SQLSTATE 23505",
 			leaked: "secret-value",
 		},
+		{
+			name:   "postgres pooler prepared statement conflict gets remediation hint",
+			err:    &pgconn.PgError{Severity: "FATAL", Code: "08P01", Message: "prepared statement name is already in use: stmt_secret-value"},
+			want:   "postgres error SQLSTATE 08P01: prepared statement conflict with a transaction-pooling proxy (PgBouncer/Neon/Supabase); other clients sharing this database must disable prepared statements, or upgrade PgBouncer to >=1.21 with max_prepared_statements enabled",
+			leaked: "secret-value",
+		},
 		{
 			name:   "clickhouse exception",
 			err:    &proto.Exception{Code: 241, Message: "Memory limit exceeded while processing 'secret-value'"},

model/main.go

@@ -138,10 +138,12 @@ func chooseDB(envName string, isLog bool) (*gorm.DB, common.DatabaseType, error)
 		if strings.HasPrefix(dsn, "postgres://") || strings.HasPrefix(dsn, "postgresql://") {
 			// Use PostgreSQL
 			common.SysLog("using PostgreSQL as database")
+			// 同时关闭 pgx 隐式与 GORM 显式预处理语句:命名 prepared statement 与
+			// 事务池代理(PgBouncer/Neon/Supabase)不兼容,会触发 FATAL 08P01/42P05。
 			db, err := gorm.Open(postgres.New(postgres.Config{
 				DSN:                  dsn,
-				PreferSimpleProtocol: true, // disables implicit prepared statement usage
+				PreferSimpleProtocol: true,
-			}), newGormConfig(true))
+			}), newGormConfig(false))
 			return db, common.DatabaseTypePostgreSQL, err
 		}
 		if strings.HasPrefix(dsn, "local") {