feat(conductor): Add run_subagent script for stable headless skill invocation

scripts/run_subagent.ps1

@@ -0,0 +1,12 @@
+param(
+    [Parameter(Mandatory=$true)]
+    [string]$Prompt,
+    
+    [string]$Model = "gemini-3-flash-preview"
+)
+
+# Ensure the session has the API key loaded
+. C:\projects\misc\setup_gemini.ps1
+
+# Piping an empty string ensures stdin is closed, forcing the Gemini CLI to terminate naturally after answering.
+echo "" | gemini $Prompt --model $Model