Restructure into pnpm monorepo with game shell, docs, and SpacetimeDB backend

- Restructure flat static prototype into pnpm workspace monorepo
- apps/game: playable shell with R3F 3D scene, HUD, SpacetimeDB connection
- apps/docs: design docs and prototypes
- apps/site: landing page
- packages/ui: shared Button and Panel primitives
- services/spacetimedb: backend module (9 tables, 11 reducers)
- Archive legacy static files to archive/legacy-static/
- Game loop: connect, undock, target, approach, dock, mine, sell
- Add pnpm-workspace.yaml, tsconfig.base.json, spacetime.json

apps/game/src/ui/TargetPanel.tsx

@@ -0,0 +1,59 @@
+import { Button, Panel } from "@void-nav/ui";
+import type { PointOfInterest, Ship } from "../module_bindings/types";
+
+export function TargetPanel({
+  ship,
+  pois,
+  selected,
+  onSelect,
+}: {
+  ship?: Ship;
+  pois: PointOfInterest[];
+  selected?: PointOfInterest;
+  onSelect: (poiId: string) => void;
+}) {
+  const current = pois.find((poi) => poi.poiId === ship?.currentPoiId);
+
+  return (
+    <Panel className="p-4">
+      <div className="flex items-start justify-between gap-3">
+        <div>
+          <p className="m-0 font-mono text-xs uppercase tracking-[0.1em] text-muted">Selected Target</p>
+          <h2 className="m-0 mt-1 text-lg leading-tight text-fg-bright">{selected?.name ?? "No target selected"}</h2>
+        </div>
+        <span className="rounded-md border border-border bg-bg-subtle px-2 py-1 font-mono text-xs uppercase tracking-[0.08em] text-fg-dim">
+          {ship?.flightMode ?? "offline"}
+        </span>
+      </div>
+
+      <dl className="mt-3 grid gap-2 text-sm">
+        <InfoRow label="Current" value={current?.name ?? "Unknown"} />
+        <InfoRow label="Target type" value={selected?.poiType.replace("_", " ") ?? "Select in scene or list"} />
+      </dl>
+
+      <div className="mt-4 grid gap-2">
+        {pois.map((poi) => (
+          <Button
+            key={poi.poiId}
+            tone={selected?.poiId === poi.poiId ? "primary" : "secondary"}
+            className="min-h-9 w-full justify-between px-3 text-left"
+            onClick={() => onSelect(poi.poiId)}
+            disabled={!ship}
+          >
+            <span className="flex-1 text-left">{poi.name}</span>
+            <span className="shrink-0 pl-3 font-mono text-xs opacity-75">{poi.poiType === "asteroid_belt" ? "Belt" : "Station"}</span>
+          </Button>
+        ))}
+      </div>
+    </Panel>
+  );
+}
+
+function InfoRow({ label, value }: { label: string; value: string }) {
+  return (
+    <div className="grid grid-cols-[5.5rem_1fr] gap-2 border-t border-border pt-2">
+      <dt className="font-mono text-xs uppercase tracking-[0.08em] text-muted">{label}</dt>
+      <dd className="m-0 text-fg">{value}</dd>
+    </div>
+  );
+}