api: GET /api/system + POST /api/explore, OpenAPI spec updated in code

app/api/explore/route.ts

@@ -0,0 +1,28 @@
+import { getGameDb } from '@/lib/db/client'
+import { ExploreError, explorePlanet } from '@/lib/game/save'
+
+// Scan one body of the current system. Body: { "planetId": number }. Returns the fresh
+// system state plus what this scan found. Costs a turn; each body can only be scanned once.
+export async function POST(req: Request) {
+  let body: unknown
+  try {
+    body = await req.json()
+  } catch {
+    return Response.json({ error: 'Invalid JSON body' }, { status: 400 })
+  }
+
+  const planetId = (body as { planetId?: unknown }).planetId
+  if (typeof planetId !== 'number' || !Number.isInteger(planetId)) {
+    return Response.json({ error: 'planetId must be an integer' }, { status: 400 })
+  }
+
+  try {
+    const db = await getGameDb()
+    return Response.json(await explorePlanet(db, planetId))
+  } catch (err) {
+    if (err instanceof ExploreError) {
+      return Response.json({ error: err.message }, { status: err.status })
+    }
+    throw err
+  }
+}