fix(crud): skip generated and read-only columns on insert and update

Read-merge-update wrote every model column back, so GENERATED ALWAYS
columns failed with SQLSTATE 428C9. Add a bun 'generated' tag option,
reflection.NonWritableColumns/RemoveNonWritableColumns, and apply them
in resolvespec, restheadspec, websocketspec, mqttspec, resolvemcp and
the nested CUD processor. Add ExcludeColumn to InsertQuery/UpdateQuery
for model-based writes.

pkg/common/adapters/database/pgsql.go

@@ -691,6 +691,13 @@ func (p *PgSQLInsertQuery) OnConflict(action string) common.InsertQuery {
 	return p
 }
 
+func (p *PgSQLInsertQuery) ExcludeColumn(columns ...string) common.InsertQuery {
+	for _, col := range columns {
+		delete(p.values, col)
+	}
+	return p
+}
+
 func (p *PgSQLInsertQuery) Returning(columns ...string) common.InsertQuery {
 	p.returning = columns
 	return p
@@ -850,6 +857,13 @@ func (p *PgSQLUpdateQuery) Set(column string, value interface{}) common.UpdateQu
 	return p
 }
 
+func (p *PgSQLUpdateQuery) ExcludeColumn(columns ...string) common.UpdateQuery {
+	for _, col := range columns {
+		delete(p.sets, col)
+	}
+	return p
+}
+
 func (p *PgSQLUpdateQuery) SetMap(values map[string]interface{}) common.UpdateQuery {
 	pkName := ""
 	if p.model != nil {