fix: testops_multi run_id handoff for pytest-xdist workers (pytest part)

[gibiw]

Pytest-only half of the two-PR split. Companion to #498 (commons).

Important

Do not merge this PR until #498 is merged and qase-python-commons 5.1.2 is published to PyPI. This PR pins qase-python-commons~=5.1.2 and will not install otherwise.

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Symptom (customer report)

Running pytest tests/examples/test_login.py -n 2 -s in testops_multi mode:

[Qase][...][info] Failed to set run id
[Qase][...][error] QaseTestOpsMulti.set_run_id() missing 1 required positional argument: 'run_id'
[Qase][...][warning] No run_id for project DW, skipping send

Workers crashed, silently fell back to the local report reporter, and dropped results from TestOps.

Root cause (pytest side)

1. QasePytestPlugin.pytest_sessionstart (controller branch) wrote the run id via str(self.run_id). In testops_multi mode self.run_id is a dict, so the lock file held "{'DW': 1553}" — not round-trippable.
2. QasePytestPlugin.load_run_from_lock (worker branch) read that string back and called self.reporter.set_run_id(self.run_id) with one positional argument, which crashed inside the commons multi reporter.

Fix in this PR

• pytest_sessionstart now writes the run id via json.dumps, so the dict shape survives the controller → worker boundary.
• load_run_from_lock parses with json.loads; the result is a dict in multi mode and a scalar (string) in single mode. Falls back to treating the raw read as a string if the file is in the legacy non-JSON format, so older lock files still load.
• The parsed value is handed to QaseCoreReporter.set_run_id, which in commons 5.1.2 dispatches dict input to QaseTestOpsMulti.set_run_ids() (the companion change in fix: testops_multi xdist run_id handoff + mask api token in config log (commons part) #498).

Dependency pin

Bumped qase-python-commons minimum from ~=5.1.1 to ~=5.1.2 in pyproject.toml. Without 5.1.2, the dict reaches the commons reporter without a matching set_run_ids() method and the fix is silently dead.

Test plan

• 115 unit tests passed, including 5 new lock-file round-trip cases:
  • Controller writes dict run id as JSON.
  • Controller writes scalar run id as JSON.
  • Worker loads dict run id and seeds the reporter with the dict.
  • Worker loads scalar run id as a string (legacy contract preserved).
  • Worker tolerates a legacy non-JSON lock file.
• 10 integration tests passed.
• End-to-end smoke against real Qase API in examples/multiproject/pytest with pytest -n 2:
  • Baseline on main: 4× missing 1 required positional argument errors, 4 silent fallback JSON files.
  • With this fix + commons fix: testops_multi xdist run_id handoff + mask api token in config log (commons part) #498: 0 errors, all 12 worker results land in TestOps DEVX #895 / DEMO #714.

Release

• Bumped qase-pytest 8.3.0 → 8.3.1.
• Pinned qase-python-commons~=5.1.2 so new installs always pull the matching commons release.

Companion PR

• Commons half: fix: testops_multi xdist run_id handoff + mask api token in config log (commons part) #498 — merge & publish first.