fix(moa): parse JSON string reference_models in _normalize_preset

[wen0531]

Problem

hermes moa list shows hardcoded default models (openai-codex:gpt-5.5, openrouter:deepseek/deepseek-v4-pro) instead of user-configured presets.

Root Cause

hermes moa configure serializes reference_models as a JSON string in config.yaml:

reference_models: '[{"provider":"xiaomi","model":"mimo-v2.5-pro"},{"provider":"minimax","model":"MiniMax-M3"}]'

But _normalize_preset expects a native list — it checks isinstance(raw_refs, list) which fails for strings, then falls back to DEFAULT_MOA_REFERENCE_MODELS.

Fix

Add json.loads() parsing before the type check in _normalize_preset, so both JSON string and native list formats work correctly.

Verification

Before fix:

$ hermes moa list
* default
  Reference models:
    1. openai-codex:gpt-5.5
    2. openrouter:deepseek/deepseek-v4-pro

After fix:

$ hermes moa list
* default
  Reference models:
    1. xiaomi:mimo-v2.5-pro
    2. minimax:MiniMax-M3
    3. deepseek:deepseek-v4-pro

[teknium1]

Thanks for the focused normalization fix. Current main does exhibit the fallback: hermes_cli/moa_config.py:132-141 treats a string reference_models value as invalid and substitutes defaults.

Problems

• The PR has no regression test. tests/hermes_cli/test_moa_config.py:82-97 covers numeric scalars and bare mappings, but not a valid JSON string containing model slots.
• The stated hermes moa configure root cause does not match current code: hermes_cli/moa_cmd.py:100-117 constructs refs as a native list, assigns it directly, normalizes it, then saves it. The confirmed use case is hand-edited or otherwise pre-existing JSON-string config.

Suggested changes

• Add a normalization test for a JSON-string list of valid slots, plus malformed JSON fallback behavior.
• Reframe the PR description around configuration tolerance rather than CLI serialization.

This is an automated hermes-sweeper review.

[teknium1]

Please add a regression test in tests/hermes_cli/test_moa_config.py covering a valid JSON-string list of reference slots (and malformed JSON fallback), since the existing non-list tests only cover scalar and mapping inputs.

[teknium1]

Merged via cluster PR #70282 (commit 9b868f6) — your commit cherry-picked with authorship preserved, plus regression tests we added for the JSON-string round-trip and malformed-string fallback. Thanks!