fix(build): give the frontend build 1GB /dev/shm

CRA's build runs fork-ts-checker in a forked process whose IPC needs
more than Docker's default 64MB /dev/shm; too little segfaults
'npm run build' (RpcIpcMessagePortClosedError / SIGSEGV) with no compile
error. Set shm_size on the frontend image build so production deploys
don't hit this. (CI runners need the same via their container options.)

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

docker-compose.yml

@@ -54,6 +54,9 @@ services:
   frontend:
     build:
       context: ./job-tracker-ui
+      # fork-ts-checker (CRA's build type-checker) needs more than Docker's default
+      # 64MB /dev/shm; too little causes a SIGSEGV during `npm run build`.
+      shm_size: '1gb'
       args:
         - REACT_APP_GOOGLE_CLIENT_ID=${AUTH_GOOGLE_CLIENT_ID}
         # Optional override; default in production is `/api`