🔒️(helm) add pod and container securityContext

This commit aim at adding a securityContext for
pod and container in Deployment and Job,
it include livekit pods as well

It adds 2 values :
- podSecurityContext : for pods
- securityContext : for containers

Please note that `celeryBackend` Deployment does
not have any values defined in `values.meet.yaml` at the moment.

src/frontend/Dockerfile

@@ -1,5 +1,7 @@
 FROM node:20-alpine AS frontend-deps
 
+USER node
+
 WORKDIR /home/frontend/
 
 COPY ./src/frontend/package.json ./package.json
@@ -8,7 +10,7 @@ COPY ./src/frontend/package-lock.json ./package-lock.json
 RUN npm ci
 
 COPY .dockerignore ./.dockerignore
-COPY ./src/frontend/ .
+COPY --chown=node:node ./src/frontend/ .
 
 ### ---- Front-end builder image ----
 FROM frontend-deps AS meet
@@ -17,6 +19,8 @@ WORKDIR /home/frontend
 
 FROM frontend-deps AS meet-dev
 
+USER node
+
 WORKDIR /home/frontend
 
 EXPOSE 8080