feat(ui): hide monitor panel by default and reduce width

- Remove auto-open of monitor panel on startup
- Reduce monitor panel width from 500px to 320px

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

src/web/public/app.js

@@ -55,8 +55,6 @@ class ClaudemanApp {
     this.loadState();
     this.loadQuickStartCases();
     this.setupEventListeners();
-    // Show monitor panel by default
-    this.toggleMonitorPanel();
     // Start system stats polling
     this.startSystemStatsPolling();
   }

src/web/public/styles.css

@@ -2345,7 +2345,7 @@ kbd {
   position: fixed;
   bottom: var(--toolbar-height);
   right: 0.5rem;
-  width: 500px;
+  width: 320px;
   max-width: calc(100vw - 1rem);
   max-height: 80vh;
   background: var(--bg-card);