feat: clean up CLI version display and add compatibility warnings

Strips the '(Claude Code)' suffix from the installed version badge so
it shows cleanly as 'CLI 2.1.50'. Also adds an italic warning message
after the supported badge when versions differ: amber text for newer
installs, red text for outdated installs.

src/lib/components/CliVersion.svelte

@@ -18,6 +18,8 @@
     return 0;
   }
 
+  let displayVersion = $derived(installedVersion.split(" (")[0]);
+
   let supportedBadgeState = $derived.by(() => {
     if (installedVersion === "Loading..." || installedVersion === "Unknown") {
       return "neutral";
@@ -61,7 +63,7 @@
       <polyline points="4 17 10 11 4 5" />
       <line x1="12" y1="19" x2="20" y2="19" />
     </svg>
-    <span class="version-text">CLI {installedVersion}</span>
+    <span class="version-text">CLI {displayVersion}</span>
   </div>
 
   <div class="cli-version supported {supportedBadgeState}" title="Highest audited CLI version">
@@ -80,6 +82,16 @@
     </svg>
     <span class="version-text">Supported {SUPPORTED_CLI_VERSION}</span>
   </div>
+
+  {#if supportedBadgeState === "ahead"}
+    <span class="version-warning ahead"
+      >Your version is newer, some features may not be supported</span
+    >
+  {:else if supportedBadgeState === "behind"}
+    <span class="version-warning behind"
+      >Your version is out of date, please update to ensure compatibility</span
+    >
+  {/if}
 </div>
 
 <style>
@@ -131,4 +143,18 @@
   .version-text {
     white-space: nowrap;
   }
+
+  .version-warning {
+    font-size: 0.75rem;
+    font-style: italic;
+    white-space: nowrap;
+  }
+
+  .version-warning.ahead {
+    color: var(--warning-color, #ff9800);
+  }
+
+  .version-warning.behind {
+    color: var(--error-color, #f44336);
+  }
 </style>