✨ refactor: streamline SSR setup and remove Babel configuration

- Updated import path for app.server module in SSR hook.
- Removed babel.config.server.json as Babel is no longer needed for async/await transformation.
- Adjusted esbuild configuration to target ESNext and modified output paths.
- Enhanced App.svelte to handle initial content loading during SSR.
- Updated SSR script to load messages synchronously before rendering.
- Simplified build:server script in package.json by removing Babel step.

package.json

@@ -12,7 +12,7 @@
         "start:mock": "MOCK=1 node scripts/esbuild-wrapper.js start",
         "start:ssr": "SSR=1 node scripts/esbuild-wrapper.js start",
         "build": "node scripts/esbuild-wrapper.js build",
-        "build:server": "node scripts/esbuild-wrapper.js build esbuild.config.server.js && babel --config-file ./babel.config.server.json _temp/app.server.js -o _temp/app.server.babeled.js && esbuild _temp/app.server.babeled.js --outfile=api/hooks/lib/app.server.js --bundle --sourcemap --platform=node --banner:js='// @ts-nocheck'",
+        "build:server": "node scripts/esbuild-wrapper.js build esbuild.config.server.js",
         "test": "playwright test",
         "test:e2e": "playwright test tests/e2e",
         "test:api": "playwright test tests/api",
@@ -23,9 +23,6 @@
         "tour:mobile": "playwright test --config=video-tours/playwright.config.ts --project=tour-mobile"
     },
     "devDependencies": {
-        "@babel/cli": "^7.28.6",
-        "@babel/core": "^7.29.0",
-        "@babel/preset-env": "^7.29.5",
         "@playwright/test": "^1.59.1",
         "@tailwindcss/postcss": "^4.3.0",
         "@tsconfig/svelte": "^5.0.8",
@@ -57,4 +54,4 @@
         "svelte-i18n": "^4.0.1"
     },
     "packageManager": "yarn@4.7.0"
-}
+}