docs(plans): record S20-A step MRs in the status table

Fill one Status table cell in the S20-A plan.

Step	Merge request
7, npm_packages and container_images tombstone scans	!1700 (merged)

Step 7 merged as !1700 (merged) on 2026-08-19. Its squash commit 2e2165b64 is on main. The Status cell for row 7 stayed empty.

An empty cell means "not yet recorded", not "not started". A reader took this empty cell for unstarted work and dispatched step 7 a second time. That run pushed a branch before it found the merged work.

A standing merge request, not a batch

The plan Status table has a single writer, so step merge requests do not edit the plan file. This merge request is that writer for S20-A. It stays open while the S20-A workstream has steps in flight. Whoever opens a step merge request adds its row here, in the same sitting.

Step 14 is in flight and has no merge request yet, so it gets no row now. Steps 15 and later follow the same rule. Rows arrive one at a time, as each step merge request opens.

Scope

This merge request records one reference. It changes no step, no scope, and no acceptance text.

This change does not touch !1780 (merged), which carries rows 12 and 13. Row 7 sits five lines above those two rows, so the two branches compose without a conflict. A local merge of both branches produced no conflict and a table with rows 7, 12, and 13 all filled.

Two cosmetic defects in the table are out of scope and stay as they are:

• Row 4 records !1513 (merged) as a full Markdown link. Every other filled row uses the bare !NNNN form.
• The step column of row 7 carries one space of padding more than the other rows. This change replaces the empty merge request cell only, and leaves that padding as it found it.

This is a bot message 🤖 — /smurfit