fix: correct Settings actions in Laya ready state and clear stale AI warning (#12)

Offer the right actions in Settings when Laya is ready/available
instead of leaving irrelevant ones, and stop showing the ChannelList
local-AI warning once the runtime is actually available. Derive both
from layaStatusPresentation and cover the ready/available action set
with tests.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

public/js/services/layaStatusPresentation.js

@@ -77,5 +77,13 @@
         };
     }
 
-    return { presentLayaStatus };
+    function channelListWarning(mode, status = {}, batchFailed = false) {
+        if (mode === 'algo') return '';
+        if (batchFailed || status.modelPresent !== true || status.runtimeAvailable !== true) {
+            return 'Local AI service is unavailable. Standard channel matching is being used.';
+        }
+        return '';
+    }
+
+    return { channelListWarning, presentLayaStatus };
 });