fix(cli): hermes config set now parses YAML lists/dicts (#64323)

[webtecnica]

Fixes #64323. Added YAML safe_load when value starts with [ or {, so docker_volumes and other list configs are stored correctly instead of as literal strings.

[alt-glitch]

This was generated by AI during triage.

Duplicate of #40546 — both add list/dict-literal parsing at the same set_config_value() site in hermes_cli/config.py (this PR uses yaml.safe_load, #40546 uses json.loads, same mechanism/site). #40546 is the earliest still-open PR for this fix. Also related to sibling #60558.

[teknium1]

Thanks for targeting a real config set failure. Current main leaves bracketed values as strings in hermes_cli/config.py:8264-8279; terminal.docker_volumes is list-typed (hermes_cli/config.py:1241) and Docker discards non-list values (tools/environments/docker.py:615-618).

Problems

• The new coercion block deletes the string-default guard from e4ea0a0ed7fc24761b2b425146893561a73216e1. The current regression suite requires approvals.mode values such as off to remain strings (tests/hermes_cli/test_set_config_value.py:256-289); this branch would coerce off to false.
• The PR patch also includes unrelated DEFAULT_CONFIG changes outside the stated parsing fix.

Suggested changes

• Preserve the string-typed guard and its tests; apply structured list/dict parsing only where it cannot reinterpret a declared string setting.
• Remove the unrelated default-config hunks and keep the salvage focused on structured config values.

Automated hermes-sweeper review.

[teknium1]

Current main intentionally preserves string-typed settings: e4ea0a0ed7fc24761b2b425146893561a73216e1 and tests/hermes_cli/test_set_config_value.py:256-289 require approvals.mode off to remain a string. This unconditional scalar coercion would write boolean false; retain the declared-string guard and parse structures only where that invariant is preserved.