Feat add parent views and breadcrumbs

[f3-jolt]

👋 TL;DR

Adds Area and Sector stat pages to complete the regional hierarchy (Nation → Sector → Area → Region → AO), plus a PWA-friendly breadcrumb/back-navigation bar, WIP disclaimers on the new pages, an Achievements card, and a unified search modal.

🔎 Details

New pages: Area & Sector

• /stats/sector/:sectorId — summary card, area breakdown table, charts scaffold
• /stats/area/:areaId — summary card, region breakdown table, charts scaffold
• Both pages are wired to new BigQuery loaders (src/lib/bq/sectors.ts, src/lib/bq/areas.ts) and expose the same filter/loader pattern as existing region/AO pages
• Skeleton loading states included (loading.tsx) for both routes

WIP disclaimer banner

• Yellow warning banner rendered below the page header on both Area and Sector pages noting the pages are not final

Breadcrumb + back navigation

• New Breadcrumb component (src/components/breadcrumb.tsx) using @heroui/breadcrumbs
• Layout: ← Back button (calls router.back()) on the left, breadcrumb trail on the right
• Added to all stat pages: Nation, Sector, Area, Region, AO, PAX
• Trails are built from data already loaded on each page — no extra BQ round-trips

✅ How to Test

• Navigate to a known Sector (/stats/sector/:id) — page renders with summary, area breakdown, breadcrumb bar, and WIP banner
• Navigate to a known Area (/stats/area/:id) — page renders with summary, region breakdown, breadcrumb bar, and WIP banner
• On any stat page, tap ← Back — confirm it returns to the previous page in history
• Confirm the breadcrumb trail shows the correct ancestor links (e.g. on an Area page: Home › Nation › {Sector Name})
• In a PWA (add to home screen), verify back navigation works correctly via the back button since the browser chrome is hidden

🥜 GIF