[fix](trx-frontend-http): move the map's fullscreen and filter toggles into the bar

Fullscreen and Hide Filters floated in their own block over the map's
top-right corner, separate from the filter bar they sit beside.

Put them at the right-hand end of the bar, behind a separator. What made
this awkward before is that Hide Filters cannot live inside the thing it
hides, so the collapse now applies to the filters alone: the bar keeps its
two controls and shrinks to them at the map's right edge, leaving the whole
map visible and the way back one click away.

Fixes #38

Signed-off-by: Stan Grams <sjg@haxx.space>

src/trx-client/trx-frontend/trx-frontend-http/assets/web/generated/map-core.js

@@ -1335,7 +1335,8 @@ var mapWindow = window;
   function applyMapOverlayPanelVisibility() {
     const panel = document.querySelector("#map-stage .map-overlay-panel");
     if (!panel) return;
-    panel.classList.toggle("is-hidden", !mapOverlayPanelVisible);
+    panel.classList.toggle("filters-hidden", !mapOverlayPanelVisible);
+    panel.querySelector(".map-overlay-filters")?.classList.toggle("is-hidden", !mapOverlayPanelVisible);
   }
   function updateMapOverlayToggleButton() {
     const btn = mapEl("map-overlay-toggle-btn");