Hardware verification backlog for the editor feature set

[BernardJen]

Several changes from epic #10 are complete and green in software but have not been run on the machine. AGENTS.md says hardware-dependent work is not done when the code typechecks, so their OpenSpec changes are deliberately left active with the ⚙ tasks unchecked. This issue is the single place to track them.

Each needs a real plot on the UUNA TEK, and each is cheap to check.

Multi-pen pauses (#3 — openspec/changes/multi-pen-plot/)

• Plot a two-pen drawing. Confirm the machine parks at the work origin with the pen up, waits, and resumes on Continue with no lost or repeated stroke.

Cutting mode (#58 — openspec/changes/cut-mode/)

• Cut a real sticker: confirm the knife depth cuts the vinyl without going through the backing, the overcut releases the piece, and a registered cut follows the print.
• Measure the blade offset on the holder, set it in the knife profile, and confirm corners come out square rather than rounded. (It ships at 0, i.e. compensation off, because a wrong offset cuts into the piece.)

Holding tabs (#63 — openspec/changes/holding-tabs/)

• Cut a sticker with tabs on: the piece should stay attached during the job and snap out cleanly by hand. Default width is 0.5 mm.

Magnet avoidance (#64 — openspec/changes/magnet-avoidance/)

• Run a job whose travel crosses a recorded magnet and confirm the carriage clears it. (Verified in software: closest approach 12.47 mm against a 12 mm keep-out.)

Registration wizard (pre-existing — openspec/changes/svg-calibration-points/)

• The four hardware tasks left over from v1.2.0 are still unchecked in that change.

Once a section passes, tick its tasks in the corresponding change and archive it.