fix: resolve all biome warnings and formatting issues

- Remove unnecessary non-null assertions where values are guaranteed
- Replace array index access with .at() for safer element retrieval
- Use local variables to avoid repeated process.env lookups
- Replace any types with unknown in functional utilities
- Use nullish coalescing for TOTP hash byte access
- Auto-format security patches to match biome config

apps/cli/src/commands/setup.ts

@@ -219,9 +219,9 @@ async function setupRouter(): Promise<ShannonConfig> {
 
   const router: ShannonConfig['router'] = { default: defaultModel };
   if (routerProvider === 'openai') {
-    router!.openai_key = apiKey;
+    router.openai_key = apiKey;
   } else {
-    router!.openrouter_key = apiKey;
+    router.openrouter_key = apiKey;
   }
 
   return { router };

apps/cli/src/commands/start.ts

@@ -65,11 +65,8 @@ export function start(args: StartArgs): void {
   const containerName = `shannon-worker-${suffix}`;
 
   // 8. Generate workspace name if not provided
-  let workspace = args.workspace;
-  if (!workspace) {
-    const hostname = new URL(args.url).hostname.replace(/[^a-zA-Z0-9-]/g, '-');
-    workspace = `${hostname}_shannon-${Date.now()}`;
-  }
+  const workspace =
+    args.workspace ?? `${new URL(args.url).hostname.replace(/[^a-zA-Z0-9-]/g, '-')}_shannon-${Date.now()}`;
 
   // 9. Resolve credentials
   const credentialsDir = getCredentialsDir();
@@ -142,7 +139,7 @@ export function start(args: StartArgs): void {
 
         // Clear waiting line and show info
         process.stdout.write('\r\x1b[K');
-        printInfo(args, useRouter, workspace!, workflowId, repo.hostPath, workspacesDir);
+        printInfo(args, useRouter, workspace, workflowId, repo.hostPath, workspacesDir);
         return;
       }
     } catch {