v0.13.1: UI polish fixes round 2 (4 fixes)

- Fix 1: deploy-cross-drive card uses correct CSS vars (--bg-secondary, --border-color)
- Fix 2: Auto-generated env values — badge inline with label, remove copy buttons, muted readonly inputs
- Fix 3: Snapshot table shows 0 instead of n/a; remove unused .col-na CSS
- Fix 4: Disk warnings moved inline under storage bars (Inline alert field, GetInlineAlerts, inline-warning CSS)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

controller/internal/web/templates/monitoring.html

@@ -63,6 +63,17 @@
         {{end}}
         {{end}}
     </div>
+    {{if .DiskWarnings}}
+    <div class="inline-warnings">
+        {{range .DiskWarnings}}
+        <div class="inline-warning inline-warning-{{.Level}}">
+            <span class="inline-warning-dot">●</span>
+            <span class="inline-warning-text">{{.Message}}</span>
+            {{if .Link}}<a href="{{.Link}}" class="inline-warning-link">{{.LinkText}} →</a>{{end}}
+        </div>
+        {{end}}
+    </div>
+    {{end}}
 </div>
 
 <!-- Section 2: Remote Monitoring Status -->