Update shell docs to correctly describe verify command

The verify command checks vault setup, authentication, and permissions - not template placeholders.

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Co-Authored-By: Claude <noreply@anthropic.com>
Co-Authored-By: Happy <yesreply@happy.engineering>

Author: 3 people

docs/guide/shell.md

@@ -219,7 +219,7 @@ All standard Keep commands work in the shell:
 
 - **`diff <stage1> <stage2>`** - Compare secrets between stages
 - **`export`** - Export secrets to .env format
-- **`verify`** - Verify template placeholders
+- **`verify`** - Verify vault setup, authentication, and permissions
 
 ### Exiting the Shell