[PROFILE-008] Remove unused profile language goals

[chev0004]

Outline

Summary

Removes the unused target-language goal field from the discovery profile type, Storybook mock data, and locale fixtures. ProfileCard never rendered goals and no real flow collects or persists them.

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Changes & Enhancements

• Type of Change:
  • Feature
  • Bugfix
  • Refactor
  • Chore
• Changes:
  • (Discovery):
    • Drop goal from DiscoveryTargetLanguage in ProfileCard.tsx.
    • Remove goal values from ProfileCard.stories.tsx and profileFixtures.ts mock profiles.
  • (i18n):
    • Remove goalConversation, goalGrammar, goalBusiness, and goalExam keys from en and ja locales.

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Page / App Changes

Affected Next.js Routes (Local):

Before (Screenshot)

After (Screenshot)

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Component / Storybook Changes

Affected Storybook Components (Local):

• Discovery/ProfileCard > Default
• Discovery/ProfileGrid > Default

Before (Screenshot)

After (Screenshot)

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Not Doing

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Other (Remarks)

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Checklists

• Code is well-documented (comments, JSDoc, etc.).
• Existing comments were updated as needed.
• No out-of-scope changes are included.
• Write TODO comments where future work is required.
• Removed unnecessary debug code (e.g., console.log, debugger).
• Self-reviewed and tested locally.