feat: add /introspect slash command (#17048)

.gemini/commands/introspect.toml

@@ -0,0 +1,16 @@
+description = "Analyze the influence of system instructions on a specific action."
+prompt = """
+# Introspection Task
+
+Take a step back and analyze your own system instructions and internal logic.
+The user is curious about the reasoning behind a specific action or decision you've made.
+
+**Specific point of interest:** {{args}}
+
+Please provide a detailed breakdown of:
+1.  Which parts of your system instructions (global, workspace-specific, or provided via GEMINI.md) influenced this behavior?
+2.  What was your internal thought process leading up to this action?
+3.  Are there any ambiguities or conflicting instructions that played a role?
+
+Your goal is to provide transparency into your underlying logic so the user can potentially improve the instructions in the future.
+"""