CI: Pack and Consumer start alongside the test legs #72

Problem

The median TypeKit run takes 16.9 minutes (p90 18.6). The critical path is the Windows test leg (8.9 min median), and only then Pack (6.0 min), because pack and consumer need the whole test matrix. Packing does not depend on the tests' outcome to run. The ordering only stops a broken build being packed, and the gate (#71) enforces that anyway.

Change

• pack and consumer need changes only, and start alongside the test and probe legs.
• The gate requires every leg, so a red test still blocks the merge.
• release.yml keeps its sequential verify.

Done when

A run's wall-clock is set by its longest leg rather than Windows followed by Pack. The estimate is about 9 to 10 minutes; measure it on the first runs and record the result here.