Make GITLAB_TOKEN and GITLAB_USERNAME optional (pair or neither) (!12) · Merge requests · Klaus Wölfel / klausagent

Previously both GITLAB_TOKEN and GITLAB_USERNAME were required, causing the process to abort if either was missing. Now they are optional:

Both set → askpass helper is created for HTTPS git auth (as before)
Neither set → git runs without askpass; may prompt or use other credential helpers
Only one set → configuration error, raises ValueError / SystemExit

Changes:

klausagent/env.py: gitlab vars are optional; error only on inconsistent pair (one set, other missing)
klausagent/tools/git_tools_server.py: _check_gitlab_env() allows neither-set; _run() skips askpass when neither is set; error only when exactly one is set
run.sh: remove hard GITLAB_TOKEN/GITLAB_USERNAME checks; add consistency check (both or neither)
README.md: document gitlab vars as optional pair
tests/test_env.py: update for optional semantics
tests/test_startup_env_check.py: update for optional semantics
tests/test_askpass.py: test_run_skips_askpass_when_no_gitlab_env
tests/test_auto_push.py: remove gitlab env mocking (no longer needed)

Make GITLAB_TOKEN and GITLAB_USERNAME optional (pair or neither)