feat(metrics): add GitHub Discussions metrics route and DiscussionsMe…

[Nareshkumawat-star]

Summary

Adds a new GitHub Discussions metrics integration to DevTrack. This includes an enhanced GraphQL-backed API route (/api/metrics/discussions) and a new interactive DiscussionsMetrics component featuring key stat cards, a category breakdown bar chart via Recharts, and a time-range selector (7d / 30d / 90d).

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#closes : #3252

Type of Change

• 🐛 Bug fix (non-breaking change that fixes an issue)
• ✨ New feature (non-breaking change that adds functionality)
• 💥 Breaking change (fix or feature that changes existing behavior)
• 📝 Documentation update
• ♻️ Refactor / code cleanup (no functional change)
• ⚡ Performance improvement
• 🔒 Security fix
• 🧪 Tests only

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What Changed

• src/app/api/metrics/discussions/route.ts: Updated the API route to fetch user discussion contributions, comments, accepted answers, and discussion nodes via GitHub GraphQL API (/graphql). Calculates answeredRate %, top 3 discussion categories, and accepts time-range parameters (days=7/30/90).
• src/components/DiscussionsMetrics.tsx: Created a client component with stat cards (Discussions Started, Comments Left, Answered Rate %), a horizontal Recharts Bar Chart (Discussions by Category), interactive time-range selector buttons, multi-account support (useAccount), loading skeletons, error states, and empty states.
• src/components/DiscussionsWidget.tsx: Updated to render DiscussionsMetrics directly within the customizable dashboard.

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How to Test

1. Navigate to the DevTrack dashboard.
2. Locate the Discussion Activity widget.
3. Click through the time range selector buttons (7d, 30d, 90d) to ensure metrics and category distribution re-fetch correctly.
4. Verify that stat cards (Discussions Started, Comments Left, Answered Rate %) and the category bar chart render accurately.

Expected result: The discussion widget dynamically updates with stat metrics, category bar chart, and time range selection.

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Checklist

• Self-reviewed my own diff
• No unnecessary console.log, debug code, or commented-out blocks
• Tested responsive layout and mobile display
• Preserved backward compatibility for legacy field names (commentsGiven, markedAsAnswer)

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Accessibility (UI changes only)

• Keyboard navigation works correctly
• Color contrast meets WCAG AA standard
• ARIA labels / roles added where needed
• Tested on mobile / responsive layout

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Additional Context

• Direct PR creation link for this branch: https://github.com/Nareshkumawat-star/devtrack/pull/new/feature/discussions-metrics

[github-actions]

GSSoC Label Checklist 🏷️

@Priyanshu-byte-coder — please apply the appropriate labels before merging:

Difficulty (pick one):

• level:beginner — 20 pts
• level:intermediate — 35 pts
• level:advanced — 55 pts
• level:critical — 80 pts

Quality (optional):

• quality:clean — ×1.2 multiplier
• quality:exceptional — ×1.5 multiplier

Validation (required to score):

• gssoc:approved — counts for points
• gssoc:invalid / gssoc:spam / gssoc:ai-slop — does not score

Type labels (type:*) are auto-detected from files and title. Review and adjust if needed.
Points formula: (difficulty × quality_multiplier) + type_bonus

[Nareshkumawat-star]

Hi @Priyanshu-byte-coder kindly review and merge it