Fix git availability crash in docs/conf.py for non-editable installs

[Copilot]

docs/conf.py called subprocess.check_output for git commands at import time with no error handling, causing hard failures when git is unavailable or the directory isn't a git repo (e.g., non-editable pip installs).

Changes

• docs/conf.py: Wrapped the three git subprocess.check_output calls in a try/except block, falling back to "Unknown" — matching the pattern already applied in iop4api/views/index.py

try:
    GIT_COMMIT_HASH = subprocess.check_output(['git', 'rev-parse', 'HEAD'], ...).decode('ascii').strip()
    GIT_BRANCH = subprocess.check_output(['git', 'rev-parse', '--abbrev-ref', 'HEAD'], ...).decode('ascii').strip()
    GIT_DESCRIBE = subprocess.check_output(['git', 'describe', '--always'], ...).decode('ascii').strip()
except (subprocess.CalledProcessError, FileNotFoundError, OSError):
    GIT_COMMIT_HASH = "Unknown"
    GIT_BRANCH = "Unknown"
    GIT_DESCRIBE = "Unknown"

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