chore: make small fixes to improve experience (#2111)

Author: spaenleh

.devcontainer/docker-compose.yml

@@ -53,6 +53,7 @@ services:
     hostname: db
     image: postgres:16.11-alpine
     restart: on-failure
+    shm_size: 1g
     ports:
       - 5432:5432
     volumes:

README.md

@@ -171,6 +171,7 @@ H5P_CONTENT_REGION=garage
 H5P_CONTENT_BUCKET=h5p-items
 H5P_CONTENT_ACCESS_KEY_ID=<your bucket key>
 H5P_CONTENT_SECRET_ACCESS_KEY_ID=<your bucket secret>
+H5P_PATH_PREFIX=h5p-content/
 
 
 ### External services configuration