fix: preserve dots in model names for OpenCode Zen and ZAI providers (#8794)

OpenCode Zen was in _DOT_TO_HYPHEN_PROVIDERS, causing all dotted model
names (minimax-m2.5-free, gpt-5.4, glm-5.1) to be mangled. The fix:

Layer 1 (model_normalize.py): Remove opencode-zen from the blanket
dot-to-hyphen set. Add an explicit block that preserves dots for
non-Claude models while keeping Claude hyphenated (Zen's Claude
endpoint uses anthropic_messages mode which expects hyphens).

Layer 2 (run_agent.py _anthropic_preserve_dots): Add opencode-zen and
zai to the provider allowlist. Broaden URL check from opencode.ai/zen/go
to opencode.ai/zen/ to cover both Go and Zen endpoints. Add bigmodel.cn
for ZAI URL detection.

Also adds glm-5.1 to ZAI model lists in models.py and setup.py.

Closes #7710

Salvaged from contributions by:
- konsisumer (PR #7739, #7719)
- DomGrieco (PR #8708)
- Esashiero (PR #7296)
- sharziki (PR #7497)
- XiaoYingGee (PR #8750)
- APTX4869-maker (PR #8752)
- kagura-agent (PR #7157)

hermes_cli/model_normalize.py

@@ -8,8 +8,9 @@ Different LLM providers expect model identifiers in different formats:
   hyphens: ``claude-sonnet-4-6``.
 - **Copilot** expects bare names *with* dots preserved:
   ``claude-sonnet-4.6``.
-- **OpenCode Zen** follows the same dot-to-hyphen convention as
-  Anthropic: ``claude-sonnet-4-6``.
+- **OpenCode Zen** preserves dots for GPT/GLM/Gemini/Kimi/MiniMax-style
+  model IDs, but Claude still uses hyphenated native names like
+  ``claude-sonnet-4-6``.
 - **OpenCode Go** preserves dots in model names: ``minimax-m2.7``.
 - **DeepSeek** only accepts two model identifiers:
   ``deepseek-chat`` and ``deepseek-reasoner``.
@@ -67,7 +68,6 @@ _AGGREGATOR_PROVIDERS: frozenset[str] = frozenset({
 # Providers that want bare names with dots replaced by hyphens.
 _DOT_TO_HYPHEN_PROVIDERS: frozenset[str] = frozenset({
     "anthropic",
-    "opencode-zen",
 })
 
 # Providers that want bare names with dots preserved.
@@ -329,6 +329,9 @@ def normalize_model_for_provider(model_input: str, target_provider: str) -> str:
         >>> normalize_model_for_provider("claude-sonnet-4.6", "opencode-zen")
         'claude-sonnet-4-6'
 
+        >>> normalize_model_for_provider("minimax-m2.5-free", "opencode-zen")
+        'minimax-m2.5-free'
+
         >>> normalize_model_for_provider("deepseek-v3", "deepseek")
         'deepseek-chat'
 
@@ -351,7 +354,16 @@ def normalize_model_for_provider(model_input: str, target_provider: str) -> str:
     if provider in _AGGREGATOR_PROVIDERS:
         return _prepend_vendor(name)
 
-    # --- Anthropic / OpenCode: strip matching provider prefix, dots -> hyphens ---
+    # --- OpenCode Zen: Claude stays hyphenated; other models keep dots ---
+    if provider == "opencode-zen":
+        bare = _strip_matching_provider_prefix(name, provider)
+        if "/" in bare:
+            return bare
+        if bare.lower().startswith("claude-"):
+            return _dots_to_hyphens(bare)
+        return bare
+
+    # --- Anthropic: strip matching provider prefix, dots -> hyphens ---
     if provider in _DOT_TO_HYPHEN_PROVIDERS:
         bare = _strip_matching_provider_prefix(name, provider)
         if "/" in bare: