/beacons gains a Leaflet map above the table showing every approved
beacon as a circle marker with a popup that links to the detail page.
New BeaconsListMap JS hook (assets/js/beacons_list_map_hook.ts) walks a
data-beacons JSON payload, fitBounds over the marker set, and mirrors
the format_freq/1 integer-comma formatting used on the detail view so
the popups match the rest of the UI. Approved/on-air beacons render
green, off-air beacons render gray. BeaconLive.Index.mount/3 now
materializes the list into an assign so it can encode it into the data
attribute; the live PubSub path keeps the map in sync on
create/update/delete.
Profile (/u/:callsign) polish: drop the hero-radio, hero-signal, and
hero-information-circle icons per request, and replace the daisyUI
`avatar placeholder` wrapper with a plain flex-centered circle so the
initial letter actually lives inside the circle instead of anchored to
the top-left corner (daisyUI 5 removed the old placeholder-centering
behavior).
Navigation ordering: in the top navbar (layouts.ex) Contacts now sits
immediately before Contact Map instead of after it. All three vertical
sidebars already had them adjacent in the correct order, so only the
horizontal nav changed.