Restrict launches to prepared runtimes (Refs #93)

tests/unit/host-availability.test.ts

@@ -15,7 +15,7 @@ const inventory = {
     cpuUsagePercent: 0,
     memoryTotal: 64 * GiB,
     memoryAvailable: 60 * GiB,
-    runtimeImages: ['image'],
+    preparedRuntimeImages: ['image'],
     libraries: [
         { id: 't5-library', state: 'ready' },
         { id: 't6-library', state: 'ready' }
@@ -46,6 +46,32 @@ afterEach(async () => {
 });
 
 describe('cached launch availability', () => {
+    it.each([{ preparedRuntimeImages: [] }, { preparedRuntimeImages: ['another:image'] }])(
+        'excludes a cached image until it is prepared ($preparedRuntimeImages)',
+        async ({ preparedRuntimeImages }) => {
+            const { heartbeat } = await import('../../src/lib/server/hosts/index.js');
+            const { launchAvailability } =
+                await import('../../src/lib/server/hosts/availability.js');
+            heartbeat(hostId, {
+                ...inventory,
+                runtimeImages: ['image'],
+                preparedRuntimeImages
+            });
+            const unavailable = launchAvailability([t5]);
+            expect(unavailable.availability).toMatchObject({
+                estimatedAvailable: 0,
+                portsAvailable: 0
+            });
+            expect(unavailable.warnings.join(' ')).toContain('Waiting for an eligible host');
+
+            heartbeat(hostId, { ...inventory, runtimeImages: ['image'] });
+            expect(launchAvailability([t5]).availability).toMatchObject({
+                estimatedAvailable: 1,
+                portsAvailable: 3
+            });
+        }
+    );
+
     it('reads cached estimates without placement, historical scans, or repeated database reads', async () => {
         const { db } = await import('../../src/lib/server/db/index.js');
         const capacity = await import('../../src/lib/server/hosts/capacity.js');