Fix devcontainer (#482)

Sorry, I'm just a devcontainer type of guy :D
The restructure of the repo to a monorepo broke some things. I think I corrected them all so far.
I had to add .pnpm-store to the root .gitignore, because the pnpm install in the container places it there. Alternatively, if that is not wanted, I could move the story via env variable afaik to another place inside the container outside of the repo.

server/.devcontainer/docker-compose.yml

@@ -3,7 +3,7 @@ services:
     image: mcr.microsoft.com/devcontainers/base:noble
     command: sleep infinity
     volumes:
-      - ..:/workspaces/drop:cached
+      - ../..:/workspaces/drop:cached
     depends_on:
       db:
         condition: service_healthy