refactor: update journal mode comment for DatabaseService and optimize CPU state check in EditorLayout

backend/src/services/DatabaseService.ts

@@ -47,8 +47,7 @@ export class DatabaseService {
 
         const dbPath = path.join(dataDir, 'sencho.db');
         this.db = new Database(dbPath);
-        // Use WAL mode for better concurrency performance
-        this.db.pragma('journal_mode = WAL');
+        // Default journal mode is safer for arbitrary Docker volume mounts than WAL
 
         this.initSchema();
     }

frontend/src/components/EditorLayout.tsx

@@ -197,10 +197,16 @@ export default function EditorLayout() {
 
               const netIO = `${formatBytes(rxRate)}/s ↓ / ${formatBytes(txRate)}/s ↑`;
 
+              // Check if values actually changed to prevent infinite re-renders
+              const newCpu = cpuPercent + '%';
+              if (prevStat && prevStat.cpu === newCpu && prevStat.ram === ramUsage && prevStat.lastRx === currentRx && prevStat.lastTx === currentTx) {
+                return prev;
+              }
+
               return {
                 ...prev,
                 [container.Id]: {
-                  cpu: cpuPercent + '%',
+                  cpu: newCpu,
                   ram: ramUsage,
                   net: netIO,
                   lastRx: currentRx,