fix(i18n): strip remaining 4 emojis from user-visible translations

- en/es ai.json image-prompt title: dropped 🖼️
- en/es auth.json magic-link email subject: dropped 🪄

Keeps terminal-style glyphs (✓ ✗ ▶ ⏸) — those are UI semantics,
not emoji decoration.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

packages/i18n/src/translations/en/ai.json

@@ -55,7 +55,7 @@
     "title": "Image generation",
     "description": "Create visuals from text descriptions using different models like SDXL or Midjourney.",
     "headline": {
-      "title": "Describe what you imagine 🖼️",
+      "title": "Describe what you imagine",
       "subtitle": "And let's make it live."
     },
     "composer": {