[aq1018]

Three e2e flakes, each pinned by a spec that fails without its fix.

• About card. It read the identity once, when it appeared, so a descriptor landing later left it on "no layout for ID 1". It now re-reads when the descriptor arrives, as the Stream tab and Live conversions already do.
• LUT test hook. The sim's writePosLut hook rejected a table written between Connected and the descriptor's arrival. It now waits out the fetch in flight, the way osc lut write has its descriptor before it writes.
• Mode before goal. pickMode waited on the Mode dropdown, but the goal control follows the servo's read-back of the mode one frame later, so a goal typed sooner went to the old mode's register. pickMode now waits for the goal readout's unit.

Merge with rebase to keep the three commits.