chore(01-03): exclude foundry-pf2e dev clone from tsconfig

- The cloned Foundry pf2e repository ships its own TypeScript source files which
  reference modules our project does not have ('@common/...', 'svelte', 'vite', 'peggy').
- That clone lives at server/prisma/data/foundry-pf2e/ (gitignored, dev-time only;
  the seed reads the JSON files at runtime, never the TS source).
- Add 'prisma/data/foundry-pf2e' to tsconfig exclude list so 'tsc --noEmit' on our
  codebase is unaffected by third-party content.

server/tsconfig.json

@@ -21,5 +21,10 @@
     "noImplicitAny": false,
     "strictBindCallApply": false,
     "noFallthroughCasesInSwitch": false
-  }
+  },
+  "exclude": [
+    "node_modules",
+    "dist",
+    "prisma/data/foundry-pf2e"
+  ]
 }