feat(environment): introduce isDefault flag for environments

- Added `isDefault` boolean column to the environment schema, defaulting to false.
- Updated environment creation and deletion logic to handle default environments, allowing the production environment to be created and renamed.
- Enhanced error handling for environment updates and deletions to prevent modifications to default environments.
- Updated UI components to reflect changes in environment selection based on the new default logic.

apps/dokploy/drizzle/0132_clean_layla_miller.sql

@@ -0,0 +1,4 @@
+ALTER TABLE "environment" ADD COLUMN "isDefault" boolean DEFAULT false NOT NULL;
+
+-- Set isDefault to true for existing production environments
+UPDATE "environment" SET "isDefault" = true WHERE "name" = 'production';