feat(/model): merge models.dev entries for lesser-loved providers (#14221)

New and newer models from models.dev now surface automatically in
/model (both hermes model CLI and the gateway Telegram/Discord picker)
for a curated set of secondary providers — no Hermes release required
when the registry publishes a new model.

Primary user-visible fix: on OpenCode Go, typing '/model mimo-v2.5-pro'
no longer silently fuzzy-corrects to 'mimo-v2-pro'. The exact match
against the merged models.dev catalog wins.

Scope (opt-in frozenset _MODELS_DEV_PREFERRED in hermes_cli/models.py):
  opencode-go, opencode-zen, deepseek, kilocode, fireworks, mistral,
  togetherai, cohere, perplexity, groq, nvidia, huggingface, zai,
  gemini, google.

Explicitly NOT merged:
  - openrouter and nous (never): curated list is already a hand-picked
    subset / Portal is source of truth.
  - xai, xiaomi, minimax, minimax-cn, kimi-coding, kimi-coding-cn,
    alibaba, qwen-oauth (per-project decision to keep curated-only).
  - providers with dedicated live-endpoint paths (copilot, anthropic,
    ai-gateway, ollama-cloud, custom, stepfun, openai-codex) — those
    paths already handle freshness themselves.

Changes:
  - hermes_cli/models.py: add _MODELS_DEV_PREFERRED + _merge_with_models_dev
    helper. provider_model_ids() branches on the set at its curated-fallback
    return. Merge is models.dev-first, curated-only extras appended,
    case-insensitive dedup, graceful fallback when models.dev is offline.
  - hermes_cli/model_switch.py: list_authenticated_providers() calls the
    same merge in both its code paths (PROVIDER_TO_MODELS_DEV loop +
    HERMES_OVERLAYS loop). Picker AND validation-fallback both see
    fresh entries.
  - tests/hermes_cli/test_models_dev_preferred_merge.py (new): 13 tests —
    merge-helper unit tests (empty/raise/order/dedup), opencode-go/zen
    behavior, openrouter+nous explicitly guarded from merge.
  - tests/hermes_cli/test_opencode_go_in_model_list.py: converted from
    snapshot-style assertion to a behavior-based floor check, so it
    doesn't break when models.dev publishes additional opencode-go
    entries.

Addresses a report from @pfanis via Telegram: newer Xiaomi variants
on OpenCode Go weren't appearing in the /model picker, and /model
was silently routing requests for new variants to older ones.

hermes_cli/model_switch.py

@@ -810,7 +810,10 @@ def list_authenticated_providers(
         get_provider_info as _mdev_pinfo,
     )
     from hermes_cli.auth import PROVIDER_REGISTRY
-    from hermes_cli.models import OPENROUTER_MODELS, _PROVIDER_MODELS
+    from hermes_cli.models import (
+        OPENROUTER_MODELS, _PROVIDER_MODELS,
+        _MODELS_DEV_PREFERRED, _merge_with_models_dev,
+    )
 
     results: List[dict] = []
     seen_slugs: set = set()  # lowercase-normalized to catch case variants (#9545)
@@ -856,8 +859,13 @@ def list_authenticated_providers(
         if not has_creds:
             continue
 
-        # Use curated list, falling back to models.dev if no curated list
+        # Use curated list, falling back to models.dev if no curated list.
+        # For preferred providers, merge models.dev entries into the curated
+        # catalog so newly released models (e.g. mimo-v2.5-pro on opencode-go)
+        # show up in the picker without requiring a Hermes release.
         model_ids = curated.get(hermes_id, [])
+        if hermes_id in _MODELS_DEV_PREFERRED:
+            model_ids = _merge_with_models_dev(hermes_id, model_ids)
         total = len(model_ids)
         top = model_ids[:max_models]
 
@@ -961,6 +969,9 @@ def list_authenticated_providers(
 
         # Use curated list — look up by Hermes slug, fall back to overlay key
         model_ids = curated.get(hermes_slug, []) or curated.get(pid, [])
+        # Merge with models.dev for preferred providers (same rationale as above).
+        if hermes_slug in _MODELS_DEV_PREFERRED:
+            model_ids = _merge_with_models_dev(hermes_slug, model_ids)
         total = len(model_ids)
         top = model_ids[:max_models]