[Integration] Baseline: FullBaselineLifecycle + ReselectBaseline failing on main (quarantine tracking)

## Summary

Two `BaselineIntegrationTests` are failing on `main` independent of any open PR. They are quarantined in the CI `integration-tests` job (via `fix/ci-integration-gate-quarantine`) to preserve merge velocity while this issue is resolved.

**Quarantine lane must trend to zero — do not add new tests without a companion tracking issue.**

## Failing tests

- `Ato.Copilot.Tests.Integration.Tools.BaselineIntegrationTests.FullBaselineLifecycle_SelectTailorInheritCrm`
- `Ato.Copilot.Tests.Integration.Tools.BaselineIntegrationTests.ReselectBaseline_ReplacesPreviousBaseline`

## Evidence

- First confirmed: CI run 33505808350 (pre-existing on `main`, not introduced by any PR)
- Also failing: run 33535952002, run 33542685428 (413 passed, 4 failed)
- Both tests fail fast (47 ms, 70 ms) — consistent with a setup/fixture failure rather than a logic timeout
- Error class: not yet confirmed locally. The fast failure suggests a `Container start failed` or seed-data conflict; run 33542685428 logs also show `SqlException: Cannot insert duplicate key row in 'OrgInheritanceDefaults'` during test host startup, which may be interfering

## Root cause hypothesis

The fast failure (47–70 ms) and concurrent `SqlException: duplicate key (AC-2)` in the same CI run suggest the Baseline test fixture may be attempting to re-seed already-seeded data in a shared in-memory SQLite instance, or the `SelectBaseline` / `ReselectBaseline` flow has a state-ordering dependency that fails when tests run in parallel. Needs local verbose run to confirm.

## Required resolution

1. Run both tests locally: `dotnet test ... --filter "FullyQualifiedName~BaselineIntegrationTests" --logger "console;verbosity=detailed"`
2. Capture full exception chain
3. Fix root cause
4. Remove both test names from the quarantine filter in `.github/workflows/ci.yml`
5. Close this issue

## Owner

Unassigned — needs owner.

Run `dotnet test ... --filter "FullyQualifiedName~BaselineIntegrationTests" --logger "console;verbosity=detailed"` locally and capture the full exception chain for the two named `BaselineIntegrationTests`. Review the fixture behavior around the reported `OrgInheritanceDefaults` duplicate-key error, then verify both tests pass and remove their names from the quarantine filter in `.github/workflows/ci.yml`.

Written by the indexing model from the issue text.