fix(fleet): strip trailing slash in fetchRemoteMeta URL construction (#444)

Nodes with a trailing slash in api_url (e.g. http://host:3000/) caused
fetchRemoteMeta to construct a double-slash URL (http://host:3000//api/meta),
which failed silently. The update-status endpoint then returned version: null
for the remote node, triggering a false "Update available" badge.

Every other URL construction in the codebase already strips the trailing
slash; this was the one call site that was missed.

backend/src/services/CapabilityRegistry.ts

@@ -93,7 +93,7 @@ export function getActiveCapabilities(): readonly string[] {
 /** Fetch /api/meta from a remote Sencho instance. Returns empty data on failure. */
 export async function fetchRemoteMeta(baseUrl: string, apiToken: string): Promise<RemoteMeta> {
   try {
-    const res = await axios.get(`${baseUrl}/api/meta`, {
+    const res = await axios.get(`${baseUrl.replace(/\/$/, '')}/api/meta`, {
       headers: { Authorization: `Bearer ${apiToken}` },
       timeout: 5000,
     });