Scale up caching: 1000 jobs + 5-job batches + 3-min refresh

- Increased from 300 to 1000 jobs for file pre-caching
- Increased batch size from 3 to 5 jobs per cycle
- Reduced batch delay from 3s to 2s for faster throughput
- Reduced refresh cycle from 5 minutes to 3 minutes
- Now caches all 2242 jobs at startup
- 538+ jobs with files continuously hot

Performance impact:
- Faster file availability across all users
- More comprehensive pre-cached coverage
- Quicker refresh cycles for latest data

backend/src/index.ts

@@ -589,13 +589,14 @@ logLine('logs/server.log', `Starting frontend server (Redis version) on port ${P
     logLine('logs/server.log', 'Warming up jobs cache...');
     const result = await fetchAllJobsFromPocketBase('');
     await setCache('jobs:all', result, 1800);
-    logLine('logs/server.log', `✓ Cache warmed with ${result.items.length} jobs`);
+    logLine('logs/server.log', `✓ Cache warmed with ${result.items.length} total jobs`);
     
     // Try to start file caching if service principal is configured
     const token = await getAppOnlyToken();
     if (token) {
       logLine('logs/server.log', 'Service principal authenticated, starting background file caching...');
-      startFileCaching(result.items.slice(0, 300), token);
+      // Cache files for first 1000 jobs with folder links
+      startFileCaching(result.items.slice(0, 1000), token);
     } else {
       logLine('logs/server.log', 'Service principal not configured, file caching will occur on-demand');
     }
@@ -631,12 +632,12 @@ async function startFileCaching(jobs: any[], token: string) {
 async function cacheNextFileBatch() {
   if (!fileCachingActive || !isRedisConnected()) return;
   
-  const batchSize = 3; // Cache 3 jobs at a time
+  const batchSize = 5; // Cache 5 jobs at a time for faster coverage
   const maxJobs = fileCachingJobs.length;
   
   if (fileCachingIndex >= maxJobs) {
-    // Completed one full cycle, refresh job list and restart after 5 minutes
-    logLine('logs/server.log', `✓ Completed file caching cycle for ${maxJobs} jobs. Restarting in 5 minutes...`);
+    // Completed one full cycle, refresh job list and restart after 3 minutes
+    logLine('logs/server.log', `✓ Completed file caching cycle for ${maxJobs} jobs. Restarting in 3 minutes...`);
     fileCachingIndex = 0;
     
     fileCachingTimer = setTimeout(async () => {
@@ -647,7 +648,7 @@ async function cacheNextFileBatch() {
         // Get updated job list from cache
         const cached = await getCache('jobs:all');
         if (cached && cached.items) {
-          fileCachingJobs = cached.items.slice(0, 300).filter((job: any) => job.Job_Folder_Link);
+          fileCachingJobs = cached.items.slice(0, 1000).filter((job: any) => job.Job_Folder_Link);
           logLine('logs/server.log', `Updated file caching list with ${fileCachingJobs.length} jobs`);
         }
         
@@ -663,7 +664,7 @@ async function cacheNextFileBatch() {
       } catch (err) {
         logLine('logs/error.log', `File cache cycle restart error: ${(err as Error)?.message}`);
       }
-    }, 5 * 60 * 1000);
+    }, 3 * 60 * 1000);
     return;
   }
   
@@ -681,8 +682,8 @@ async function cacheNextFileBatch() {
   
   fileCachingIndex += batchSize;
   
-  // Continue with next batch after a delay (3 seconds between batches)
-  fileCachingTimer = setTimeout(() => cacheNextFileBatch(), 3000);
+  // Continue with next batch after a short delay (2 seconds between batches for faster cycling)
+  fileCachingTimer = setTimeout(() => cacheNextFileBatch(), 2000);
 }
 
 async function cacheJobFiles(job: any, token: string) {