Print a single label at a chosen ULINE sheet cell

The single-label page gains an Output toggle (standalone vs place on a
ULINE 6-up sheet) with a 2x3 cell picker, so one label can be printed
into the correct physical position on a partially-used sheet - the
single-label equivalent of the batch page start-cell offset. Batch page
unchanged.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

CHANGELOG.md

@@ -10,6 +10,19 @@ ADR-007 and ADR-002.
 
 ## [Unreleased]
 
+### Added
+
+- Single-label sheet-position printing. The single asset-label page
+  (`/print/asset-label/:assettype/:id`) gained an Output control that toggles
+  between the standalone label (unchanged default) and placing that one label at
+  a chosen cell (1-6, via a 2x3 grid picker) of a ULINE 6-up sheet, leaving the
+  other five cells blank. This prints a single label onto the correct physical
+  spot of a partially-used sheet instead of wasting a fresh sheet, mirroring the
+  legacy shopdb behavior and complementing the batch page's start-cell offset.
+  The ULINE 6-up cell layout and dimensions are replicated from
+  `AssetLabelBatch.vue` (left untouched); encode resolution stays shared via
+  `assetLabel.js`.
+
 ## [0.7.0] - 2026-07-12
 
 ### Added