* fix(macos): keep Canvas hidden for agent content operations
Agent canvas.evalJS, canvas.snapshot, and canvas.a2ui.* commands routed
through CanvasManager.show, which re-presented the panel and called
NSApp.activate(ignoringOtherApps:) on every content update. After a
gateway restart the hosted A2UI page is dead, so the next agent push
always re-opened a panel the user had closed and stole focus.
Content operations now use a non-presenting ensureController/prepare
path; only canvas.present, canvas.navigate, and user actions reveal the
panel. Snapshot is read-only: it requires a visible matching panel and
returns CANVAS_HIDDEN instead of mutating panel state (WebKit cannot
render ordered-out windows).
* chore(i18n): refresh native inventory line offsets
ed2284c31a
