Feat/dashboard v1

[asavage111]

This pull request adds a new Dashboard page at /dashboard based on the JSONC spec created for this feature.

What was implemented

• Fully responsive dashboard page with:
  • KPI section
  • Cash flow chart
  • Recent transactions table
  • Accounts and budgets cards
• Navigation and app shell integrated with existing layout
• Mock data extracted into data/dashboard/mockData.ts
• Tailwind only — no new UI libraries
• Light/Dark mode support
• Built and linted cleanly

Verification

• npm run lint passed (warnings only in unrelated landing components)
• npm run build passed successfully
• Local dev preview renders /dashboard

Notes

• This is v1 of the dashboard UI. We will follow up with refactors to break out reusable components and refine visual polish.

✔️ Dashboard renders in local dev
✔️ Integration with global layout/navigation
✔️ No unrelated routes changed
✔️ Mock data is separated