feat(dashboard): implement producer earnings dashboard with analytics and charts (#18)

[Simultech369]

Summary of Changes

This pull request resolves #18 by transforming the Profile page into a full-fledged Producer Earnings & Analytics Dashboard, complete with lifetime revenue metrics, monthly growth tracking, SVG area revenue charts, beat sales performance tables, and historical withdrawal logs.

🎯 Key Implementations

1. Earnings Overview Stat Cards (src/components/StatsCard.tsx)

   • 4 responsive stat cards in a top row:
     • Total Earned (Lifetime): Cumulative volume across contract earnings and local withdrawal history with mini sparkline.
     • This Month's Revenue: Current month volume with percentage growth indicator (↑ 12% vs prior month).
     • Pending Withdrawal: Live unclaimed balance from get_earnings with one-click claim action.
     • Total Sales: Lifetime count of license purchases across producer's beats.

2. Interactive SVG Revenue Trend Chart (src/components/RevenueChart.tsx)

   • Pure SVG area and line chart with gradient fill (0 external charting dependencies).
   • Timeframe toggles for 30d, 90d, and 1y periods.
   • Interactive point hover tooltips showing exact date, XLM amount, and sales count.
   • Clean empty state with CTA to upload beats.

3. Beat Performance Table (src/components/BeatPerformanceTable.tsx)

   • Catalog table of all beats uploaded by the producer with Title, Genre, BPM, Sales count, and estimated Revenue in XLM.
   • Sortable columns (Title, BPM, Sales, Revenue).
   • Gold border highlight and badge for the feat: implement audio waveform visualization in SampleCard #1 top-performing beat.

4. Recent Sales Activity Feed (src/components/SalesFeed.tsx)

   • Real-time recent transaction list displaying buyer address (truncated), license tier pill (Lease, Premium, Exclusive), XLM volume, relative timestamps, and direct Stellar block explorer links.

5. Withdrawal History Log (src/components/WithdrawalHistory.tsx)

   • Historical withdrawals table with Date, XLM amount, Tx Hash linking to explorer, and Confirmed status badge.

6. Analytics Service & Custom Hook (src/services/analytics.ts, src/hooks/useProducerStats.ts)

   • Daily bucket aggregation (aggregateSalesByDay), growth rate calculations (calculateGrowth), and scoped localStorage persistence per connected wallet address.

7. Contract Integration (src/contracts/crate.ts)

   • Added getSamplesByUploader querying producer samples from the contract.

---

🧪 Verification & Testing

• npx vitest run: