Adapt container for new optional requirements (#420)

## Summary

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Install all extras in the container and add `ffmpeg`.

---

- [x] "I certify that all code in this PR is my own, except as noted
below."

## Use of AI

- [ ] Includes AI-assisted code completion
- [ ] Includes code generated by an AI application
- [ ] Includes AI-generated tests (NOTE: AI written tests should have a
docstring that includes `## WRITTEN BY AI ##`)

Author: sjmonson

Containerfile

@@ -31,19 +31,28 @@ COPY / /src
 
 # Install guidellm and locked dependencies
 RUN pdm use -p /src -f /opt/app-root \
-    && pdm install -p /src --check --prod --no-editable
+    && pdm install -p /src -G all --check --prod --no-editable
 
 # Prod image
 FROM $BASE_IMAGE
 
+# Switch to root for installing packages
+USER root
+
+# Install some helpful utilities and deps
+RUN dnf install -y --setopt=install_weak_deps=False \
+        vi tar rsync ffmpeg-free \
+    && dnf clean all
+
+# Switch back to unpriv user
+# Root group for k8s
+USER 1001:0
+
 # Add guidellm bin to PATH
 # Argument defaults can be set with GUIDELLM_<ARG>
 ENV HOME="/home/guidellm" \
     GUIDELLM_OUTPUT_PATH="/results/benchmarks.json"
 
-# Make sure root is the primary group
-USER 1001:0
-
 # Create the user home dir
 WORKDIR $HOME