[AIGTWY-4972] Consolidate CUJ helpers, fix flakes, parallelize CUJs

[david-siqi-liu]

The e2e CUJs grew one copy of each helper per journey. This consolidates the shared helpers so CUJ 7 (#930) and #1014 / #1015 can build on one version, and fixes three recurring CUJ flakes found in recent CI runs.

Shared helpers (behavior preserving; every assertion, timeout and threshold is unchanged unless listed under behavior changes):

• UserSession.revert_machine_wide replaces the class teardown revert and CUJ 3's two per-test copies (same terminal names and messages).
• base.make_workspace_client and base.bearer replace the per-CUJ client and bearer code. CUJ 6 now honours CLIENT_ID_ENV / CLIENT_SECRET_ENV.
• Terminal drives bare ug (agent=), and Terminal.wait_until is the one permission-rejecting wait for CUJ 2, 3 and 6. CUJ 1 keeps AgentTerminal.wait_for_task, which approves the read-only find prompt Claude emits in CI.
• evidence.assert_models / assert_served replace CUJ 1's native-model check and the CUJ 2 / CUJ 3 served-response checks. Per-CUJ thresholds and matchers stay local.
• Workspace.agent_configs splits a published config by agent for CUJ 4, 5 and 6. CUJ 5 reads the config through workspace.config() instead of a raw GET.
• helpers/poll.py is the one bounded poll for the CUJ 1 and CUJ 6 trace waits (same budgets) and the ug mcp list retry. Trace SQL stays on tests/integration/utils/sql.py.
• helpers/mcp.py (registered_name), evidence.claude_file_task, and shared model and header constants in helpers/constants.py.

Reliability fixes:

• MCP registration (Claude), failing 3 of 13 recent runs: Claude returned correct receipts but keyed them mcp__server__tool, and on this PR's first run echoed each raw {"result": "<sha>"} tool result. The prompt names the exact keys, and the check accepts exactly those two native shapes. The receipt values and key set must still match exactly.
• ug mcp list health row (claude:failed, 1 of 13): Claude's single-shot probe raced the proxy cold start. The test polls up to 90s until the rows match, then runs the same exact assertion.
• CUJ 4 Claude tasks use the absolute-path prompt CUJ 3 already used, so Claude no longer searches with find and hits a permission prompt.
• Teardown leaks: a class that leaves /etc agent files still fails, and later classes now name that class and those paths instead of a generic dirty-runner error.
• The CUJ bearer is refreshed per test (classes such as catalog discovery can outlive the M2M token). Every bearer a session installs stays redacted in artifacts.
• ug review: max_output_tokens 4,000 to 16,000. High-effort reasoning consumed the old budget, leaving "returned no output text". The error now includes incomplete_details.reason.

CI:

• E2E CUJs run one runner per file, checked as E2E CUJs · <CUJ_NAME> (for example E2E CUJs · CUJ 3 · UC model discovery, names from the CUJ plan doc). CUJs share machine-wide /etc agent settings, so they cannot run concurrently on one runner. Each file still runs against its own read-only workspace, with fail-fast: false, and All integration tests requires every shard.
• A small plan job discovers every tests/e2e_cuj/test_*.py and reads its module-level CUJ_NAME, so adding a CUJ needs no workflow edit (and no .github/ owner approval). A file without CUJ_NAME fails the plan job; a unit contract test runs the same discovery script and also enforces unique names and the test_cuj<N>_<topic>.py / CUJ <N> · convention.
• The CUJ runners set UV_HTTP_TIMEOUT=120 and UV_HTTP_RETRIES=6. All of them install from PyPI at once, and one shard already failed on a metadata fetch timeout.
• CUJ files are renamed to test_cuj<N>_<topic>.py:
  • CUJ 1: test_cuj1_explicit_models.py (was test_ug_managed_sentinel.py)
  • CUJ 2: test_cuj2_mps_mcp.py, test_cuj2_skills.py
  • CUJ 3: test_cuj3_models.py (was test_catalog_discovery.py), test_cuj3_mcp.py (was test_mcp_registration.py), test_cuj3_skills.py
  • CUJ 4: test_cuj4_smart_routing.py; CUJ 5: test_cuj5_budget_defaults.py; CUJ 6: test_cuj6_repeated_config.py

Behavior changes worth a look:

• CUJ 2 Claude now rejects "Do you want to proceed?" like every other CUJ (it previously waited out the timeout).
• The CUJ 6 Codex span poll's last query lands at the 300s deadline rather than up to 15s after it.

Testing:

• tests/test_e2e_cuj_helpers.py adds offline tests for the new helpers. Terminal tests run the real driver on a PTY against a fake ug.
• Full unit suite and --collect-only (78 CUJ tests) pass locally. The E2E CUJs lane is the live check.

CI timing, measured from job start and end times (main run 37821776097 vs this PR's run 37822258143):

• E2E CUJs: 19.5 min as one job, now 7.8 min wall across 9 parallel shards. Total runner time is about the same (21.9 min).
• Longest shard: CUJ 6 at 7.8 min. All others take 1.2 to 3.0 min.
• Whole CI run: 20.0 min, now 18.7 min. Full journeys · Claude (about 13 to 15 min) is now the critical path, so cutting CUJ time further won't shorten CI.

Not included: the workspace URL normalization in src/ucode from AIGTWY-4972 (a product behavior change, separate PR).

This pull request and its description were written by Isaac.

[github-actions]

UG review

The visible patch affects CUJ authentication refresh and cleanup, shared polling and evidence helpers, per-file CI sharding, and review-bot response limits. No actionable issues were identified in the provided changes.

No actionable findings.

Some patches were unavailable or truncated to fit the review context. Treat this as a partial review.

Automated advisory review of 596298f60527 using Lilly's UG review rubric. It does not approve or block this PR.

[lilly-luo]

confirmed w my ai that there are no coverage regressions, only coverage expansions 🔥