feat: initial finance SPA — phases 1 & 2

Next.js 16 personal finance dashboard connected to postgres-personal.

Phase 1 (Foundation):
- API routes: GET /api/transactions (paginated, filterable, sortable),
  GET /api/statements, GET /api/merchants
- Transactions data table with date/category/bank/search filters, pagination, sort
- Statements card grid with period, due date, amount, transaction count
- Sidebar layout with nav for all planned sections

Phase 2 (Normalisation):
- PATCH /api/transactions/[id] — upsert transaction_overrides
- POST /api/transactions/bulk — bulk categorize/normalize
- Inline click-to-edit category (22 options) and merchant name
- Blue dot override indicator, bulk action bar
- Effective values via COALESCE(override, llm_value) pattern

Stack: Next.js 16 (App Router, standalone), Prisma 7.x + @prisma/adapter-pg,
TanStack Query, Tailwind CSS. Auth via Traefik chain-oauth@file.

src/app/globals.css

@@ -1,26 +1,6 @@
 @import "tailwindcss";
 
-:root {
-  --background: #ffffff;
-  --foreground: #171717;
-}
-
 @theme inline {
-  --color-background: var(--background);
-  --color-foreground: var(--foreground);
   --font-sans: var(--font-geist-sans);
   --font-mono: var(--font-geist-mono);
 }
-
-@media (prefers-color-scheme: dark) {
-  :root {
-    --background: #0a0a0a;
-    --foreground: #ededed;
-  }
-}
-
-body {
-  background: var(--background);
-  color: var(--foreground);
-  font-family: Arial, Helvetica, sans-serif;
-}