fix(gui): Skip empty strings in selectable to prevent ImGui ID assertion

Empty strings in bias_profiles.keys() and personas.keys() caused
imgui.selectable() to fail with 'Cannot have an empty ID at root of
window' assertion error. Added guards to skip empty names.

.opencode/agents/general.md

@@ -1,7 +1,7 @@
----
+---
 description: General-purpose agent for researching complex questions and executing multi-step tasks
 mode: subagent
-model: MiniMax-M2.5
+model: minimax-coding-plan/MiniMax-M2.7
 temperature: 0.3
 ---
 
@@ -81,4 +81,4 @@ Return detailed findings with evidence:
 
 ### Recommendations
 - [Suggested next steps if applicable]
-```
+```