Add fleet and per-host concurrency controls

src/lib/server/hosts/preparation.ts

@@ -8,7 +8,7 @@ import { scheduleAvailabilityRefresh } from './availability.js';
 
 const activeStates = ['pending', 'accepted', 'running', 'unknown'];
 const supersededDownload = 'Superseded by newer game files before delivery to the host.';
-type PreparationOperation = { id: string; sequence: number; state: HostOperationState; updated_at: string; error: string | null };
+type PreparationOperation = { id: string; sequence: number; last_delivered_at: string | null; state: HostOperationState; updated_at: string; error: string | null };
 type Target = { item: HostPreparationItem; image?: string; versionId?: string; requiredBytes: number; operation?: PreparationOperation };
 type QueuedSelection = { libraryId: string; image: string | null };
 type LibraryTarget = Pick<ReturnType<typeof latestPublishedLibraries>[number], 'id' | 'sizeBytes' | 'manifestSha256'> & { name: string; queued?: boolean };
@@ -50,7 +50,7 @@ function targetLibraries(selections: QueuedSelection[]): LibraryTarget[] {
 }
 
 function latestOperation(hostId: string, kind: string, field: string, value: string): PreparationOperation | undefined {
-    return db().prepare(`SELECT id,rowid AS sequence,state,updated_at,error FROM ec_host_operations
+    return db().prepare(`SELECT id,rowid AS sequence,last_delivered_at,state,updated_at,error FROM ec_host_operations
         WHERE host_id=? AND kind=? AND json_extract(payload,?)=? ORDER BY created_at DESC,rowid DESC LIMIT 1`)
         .get(hostId, kind, `$.${field}`, value) as PreparationOperation | undefined;
 }
@@ -117,7 +117,9 @@ function targets(host: Host): Target[] {
         if (blocker) { Object.assign(target.item, blocker); continue; }
         if (operation && activeStates.includes(operation.state)) {
             target.item.state = 'preparing';
-            target.item.detail = operation.state === 'unknown' ? 'Waiting for the agent to reconcile interrupted preparation.'
+            target.item.detail = !target.image && operation.state === 'pending' && !operation.last_delivered_at
+                ? 'Queued for game-file preparation; waiting for agent delivery or fleet preparation capacity.'
+                : operation.state === 'unknown' ? 'Waiting for the agent to reconcile interrupted preparation.'
                 : target.image ? 'Downloading the runtime automatically.'
                 : target.item.cache?.status === 'verifying' ? 'Download complete. Verifying all game files.' : 'Downloading game files. Verification starts after all files arrive.';
         } else if (operation && Date.parse(host.lastHeartbeat!) <= Date.parse(operation.updated_at)) {