fix(docker): handle unlimited cgroup v2 memory

[nightcityblade]

Summary

Fixes #2123.

Handle cgroup v2's memory.max sentinel before integer conversion. Unlimited cgroup-v2 containers now report their own memory usage as a percentage of host capacity instead of falling through to the unrelated host-wide usage percentage. The existing finite-limit and cgroup-v1 paths remain unchanged.

List of files changed and why

• deploy/docker/utils.py - parse the cgroup-v2 max sentinel explicitly and preserve numeric cgroup limit handling.
• deploy/docker/tests/test_utils_memory.py - add a focused regression test for an unlimited cgroup-v2 container.

How Has This Been Tested?

• Installed the Docker test dependencies from deploy/docker/requirements.txt into a Python 3.12 environment.
• .venv/bin/python -m pytest deploy/docker/tests/test_utils_memory.py -q — 1 passed.
• uvx ruff check --select E9,F63,F7,F82 --ignore F821 deploy/docker/utils.py deploy/docker/tests/test_utils_memory.py — passed.
• uvx ruff format --check deploy/docker/tests/test_utils_memory.py — passed.
• .venv/bin/python -m compileall -q deploy/docker/utils.py deploy/docker/tests/test_utils_memory.py — passed.
• git diff --check — passed.

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas — N/A; no complex logic was introduced.
• I have made corresponding changes to the documentation — N/A; this corrects behavior already described by the existing docstring.
• I have added/updated unit tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes