feat: add translation messages for en, fr, es, it

messages/en.json

@@ -0,0 +1,31 @@
+{
+  "meta": {
+    "title": "Ombrora — Video downloader"
+  },
+  "home": {
+    "heading": "Ombrora",
+    "urlLabel": "Video URL",
+    "format": "Format",
+    "quality": "Quality",
+    "subtitles": "Download subtitles (fr, en)",
+    "advanced": "Advanced options (optional, JSON)",
+    "submit": "Download",
+    "submitting": "Sending...",
+    "errorRateLimit": "Too many submissions. Try again in an hour.",
+    "errorGeneric": "Submission error."
+  },
+  "status": {
+    "heading": "Download status",
+    "notFound": "Download not found.",
+    "loading": "Loading...",
+    "pending": "Pending",
+    "processing": "Processing...",
+    "polling": "This page refreshes automatically every 5 seconds.",
+    "ready": "Download ready",
+    "download": "Download",
+    "linkExpires": "Link valid until",
+    "failed": "Download failed.",
+    "deleted": "The file has expired and was deleted. The download is no longer available.",
+    "unknown": "Unknown status"
+  }
+}