feat(polarion): add automated Polarion test case sync

[rnetser]

What this PR does / why we need it:

Adds scripts/polarion_sync/ package that automatically creates Polarion test cases for new tests on PR merge. Intended to run as a Jenkins post-merge job (triggered by shmee webhook).

Three-stage pipeline:

1. Scan — AST-based detection of tests missing @pytest.mark.polarion markers (including parametrized tests)
2. Create — Creates Polarion TestCase work items via pylero, resolves Jira→Epic→Polarion requirements
3. Inject + Push — Injects @pytest.mark.polarion("CNV-XXXXX") markers, validates diff, pushes to main

Key features:

• Sibling test case fallback for requirement linking
• All-or-nothing push gate with strict diff validation
• Follow-up PR creation when requirement linking fails (assigned to original PR author)
• Idempotent injection (skips existing markers)
• SSL verification configurable via POLARION_DISABLE_SSL_VERIFY env var
• 25 unit tests covering scanner, injector, client, and push gate

Usage:

# Dry-run:
uv run python -m scripts.polarion_sync.main --dry-run

# Scan only:
uv run python -m scripts.polarion_sync.main --scan-only --scan-all

# Jenkins CI:
uv run python -m scripts.polarion_sync.main --pr-author <user> --pr-number <num>

Assisted-by: Claude noreply@anthropic.com

Which issue(s) this PR fixes:

Special notes for reviewer:

• Lazy imports for pylero/jira are intentional — pylero crashes on import without ~/.pylero config
• # noqa: PLC0415 on lazy imports explicitly requested by maintainer
• except Exception on pylero/jira API calls falls under AGENTS.md exception fix: preserve full module path in pytest marker analyzer ImportVisitor #5 (unversioned external libraries)

jira-ticket: