feat(kit): render the status badges and empty states with UiBadge and UiEmpty

UiBadge takes a tone and carries Core's gev-status-badge class, with
the density variants and colours left to its callers; the CCTV source and
calibration badges and the rail card badges render through it. UiEmpty takes
a title and hint, with the title as the line itself, since Core's
empty states are one line; the Scene shot list, mission roster and imagery
strip use it.

src/ui/kit/UiBadge.vue

@@ -0,0 +1,16 @@
+<script setup>
+// Core's read-only badge, with @halfpixel/ui-vue UiBadge's `tone` and classes
+// so the two kits can merge. It carries Core's `gev-status-badge` class, and
+// callers add its density variants (`gev-status-badge--box`, `--plain`) and
+// the feature classes that colour it; the kit classes carry no Core styles
+// yet. Not mirrored yet: pulse, busy, the tone glyphs and the clipped title.
+defineProps({
+  tone: { type: String, default: 'neutral' },
+});
+</script>
+
+<template>
+  <span class="ui-badge gev-status-badge" :class="`ui-badge--${tone}`"
+    ><slot
+  /></span>
+</template>