fix(types): drop the 2017 @types/date-fns stub shadowing date-fns 3 types

The tsconfig "types" array forced @types/date-fns@2.5.3 — a deprecated stub
for date-fns v2.5 — over the real types shipped by date-fns 3.6, producing
phantom errors everywhere dates are formatted (Locale unknown, format()
refusing its options argument, parseISO missing). Removing the stub and the
types entry (plus the unused node-fetch entry) clears them at the root.

Also applies the non-breaking npm audit fixes: 16 production vulnerabilities
down to 2 (drizzle-orm and xlsx, both needing review — see commit history).

TypeScript errors: 261 → 177.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01FHdE9nEh8zHhQNGpCgrtYe

package.json

@@ -109,7 +109,6 @@
     "@tailwindcss/typography": "^0.5.15",
     "@tailwindcss/vite": "^4.1.3",
     "@types/connect-pg-simple": "^7.0.3",
-    "@types/date-fns": "^2.5.3",
     "@types/express": "^4.17.21",
     "@types/express-session": "^1.18.0",
     "@types/node": "^20.16.11",