Backend POST /api/topology/set-parent already shipped; the dashboard
was missing the operator surface to drive it. Adds two affordances
to the SW4RM tab's selection bar (alongside the existing R3ST4RT /
ST0P / ST4RT / R3BU1LD / DESTR0Y / PURG3 actions):
- '⇡ M0V3 → ROOT' (bulk): promote selected agents to top-level
(parent=null). Disabled when all selected are already at root or
the selection includes the manager (backend refuses anyway).
- '⇢ M0V3 → [pick]' (single-agent only): inline <select> dropdown
+ button pair. Dropdown lists every container that isn't the
target nor a descendant of it (client-side BFS via the existing
c.parent map). On submit POSTs form-encoded
'child=<name>&new_parent=<target>' to /api/topology/set-parent;
the backend re-checks the cycle invariant and re-emits a
container snapshot so the tree repaints without a reload.
Both POSTs hit a single URL, so addBulkButton grew an optional
'perAgentBodyFor(name)' hook to handle the body-driven endpoint
shape (vs the URL-suffix /start/<name> shape every other action
uses). Lifecycle endpoints unchanged.
Mauve chrome (var(--mauve)) reads as 'structural change' rather
than the destructive red / amber of destroy / rebuild.
closes#486
2950a7f9ee