feat(ui): render the imagery split dividers from a store

createImagerySplit keeps the divider's value, drag, keyboard, CSS position
and scene split, and publishes its line to the imagery split store.
ImagerySplitView, in the scene chrome, teleports each line to the body, so
recent imagery and the Bhote Koshi event no longer build divider DOM.

scripts/package-boundaries.json

@@ -92,7 +92,9 @@
       "src/ui/rail/focusSafeChildren.js",
       "src/ui/rail/fieldValue.js",
       "src/ui/rail/statusText.js",
-      "src/voice/control.js"
+      "src/voice/control.js",
+      "src/ui/views/panels/ImagerySplitView.vue",
+      "src/ui/stores/imagerySplit.js"
     ],
     "external": ["vue", "pinia"]
   },
@@ -2992,7 +2994,8 @@
       "src/ui/stores/sceneSharing.js",
       "src/ui/stores/voice.js",
       "src/ui/stores/location.js",
-      "src/ui/stores/display.js"
+      "src/ui/stores/display.js",
+      "src/ui/stores/imagerySplit.js"
     ],
     "external": [
       "hls.js",
@@ -3578,7 +3581,9 @@
       "src/layers/streetLevel/providers/mapillary/policy.js",
       "src/data/geoImportImages.js",
       "src/data/geoImportPins.js",
-      "src/data/geoFileImport.js"
+      "src/data/geoFileImport.js",
+      "src/ui/stores/imagerySplit.js",
+      "src/ui/vueRuntime.js"
     ],
     "external": [
       "hls.js",
@@ -3589,7 +3594,9 @@
       "pbf",
       "mgrs",
       "mapillary-js",
-      "@jtarrio/webrtlsdr"
+      "@jtarrio/webrtlsdr",
+      "vue",
+      "pinia"
     ]
   },
   "application-operations": {