Merge PR #773: feat(cli,gateway): add /personality none and custom personality support

Authored by teyrebaz33. Closes #643.

- /personality none/default/neutral clears system prompt overlay
- Dict format personalities with description, tone, style fields
- Works in both CLI and gateway
- 18 tests

hermes_cli/config.py

@@ -201,6 +201,10 @@ DEFAULT_CONFIG = {
     "command_allowlist": [],
     # User-defined quick commands that bypass the agent loop (type: exec only)
     "quick_commands": {},
+    # Custom personalities — add your own entries here
+    # Supports string format: {"name": "system prompt"}
+    # Or dict format: {"name": {"description": "...", "system_prompt": "...", "tone": "...", "style": "..."}}
+    "personalities": {},
 
     # Config schema version - bump this when adding new required fields
     "_config_version": 6,