chore: drop deprecated baseUrl from server tsconfig

paths now resolves "@/*" relative to tsconfig dir as "./src/*".
moduleResolution: "node" stays (still needs ignoreDeprecations: "6.0") —
migrating to node16/nodenext requires adding .js extensions throughout
the server codebase, deferred until TS7 lands.

Author: prih

tsconfig.json

@@ -6,9 +6,8 @@
     "moduleResolution": "node",
     "outDir": "dist",
     "rootDir": "src",
-    "baseUrl": "src",
     "paths": {
-      "@/*": ["./*"]
+      "@/*": ["./src/*"]
     },
     "strict": true,
     "noUnusedLocals": true,