chore(models): sync opencode-go static fallback to core's curated list

The WebUI fallback list mirrors Hermes core's curated opencode-go list
(hermes_cli/models.py, synced 2026-08-20/21 against the live
/zen/go/v1/models endpoint and the public Go docs). Core owns the sync
duty; WebUI only mirrors. Adds the nine ids core gained since the
2026-07-07 snapshot (kimi-k3, gpt-5.6-luna, glm-5.3, grok-4.5,
qwen3.8-max, hy3, hy3-preview, muse-spark-1.2-contributor,
ox-alpha-free) and reorders to core's order so future diffs are
mechanical. Snapshot test updated accordingly.

tests/test_issue5311_opencode_go_live_models.py

@@ -165,3 +165,80 @@ def test_opencode_go_config_allowlist_still_wins(monkeypatch, tmp_path):
 
     assert calls == []  # probe never consulted
     assert _ids(group) == ["glm-5"]
+
+
+# ── Static fallback list contract ─────────────────────────────────────
+# The remaining tests pin the offline fallback list itself. It is an exact
+# mirror of Hermes core's curated ``opencode-go`` list
+# (hermes_cli/models.py) — core owns the sync duty against the live
+# https://opencode.ai/zen/go/v1/models endpoint and
+# https://opencode.ai/docs/go/, and WebUI only mirrors. This catches drift
+# in either direction: ids core added (kimi-k3, gpt-5.6-luna, glm-5.3,
+# grok-4.5, qwen3.8-max, hy3, hy3-preview, muse-spark-1.2-contributor,
+# ox-alpha-free) and ids core dropped.
+
+import ast
+from pathlib import Path
+
+ROOT = Path(__file__).resolve().parent.parent
+CONFIG_PATH = ROOT / "api" / "config.py"
+CONFIG = CONFIG_PATH.read_text(encoding="utf-8")
+
+EXPECTED_OPENCODE_GO_MODEL_IDS = [
+    "kimi-k3",
+    "kimi-k2.7-code",
+    "kimi-k2.6",
+    "kimi-k2.5",
+    "gpt-5.6-luna",
+    "grok-4.5",
+    "glm-5.3",
+    "glm-5.2",
+    "glm-5.1",
+    "glm-5",
+    "mimo-v2.5-pro",
+    "mimo-v2.5",
+    "mimo-v2-pro",
+    "mimo-v2-omni",
+    "minimax-m3",
+    "minimax-m2.7",
+    "minimax-m2.5",
+    "deepseek-v4-pro",
+    "deepseek-v4-flash",
+    "qwen3.8-max",
+    "qwen3.7-max",
+    "qwen3.7-plus",
+    "qwen3.6-plus",
+    "qwen3.5-plus",
+    "hy3",
+    "hy3-preview",
+    "muse-spark-1.2-contributor",
+    "ox-alpha-free",
+]
+
+
+def _opencode_go_static_models():
+    tree = ast.parse(CONFIG, filename=str(CONFIG_PATH))
+    for node in tree.body:
+        if not isinstance(node, ast.Assign):
+            continue
+        if not any(isinstance(target, ast.Name) and target.id == "_PROVIDER_MODELS" for target in node.targets):
+            continue
+        provider_models = ast.literal_eval(node.value)
+        return provider_models["opencode-go"]
+    raise AssertionError("_PROVIDER_MODELS assignment not found")
+
+
+def test_opencode_go_static_models_match_core_curated_list():
+    models = _opencode_go_static_models()
+    assert [model["id"] for model in models] == EXPECTED_OPENCODE_GO_MODEL_IDS
+
+
+def test_opencode_go_recent_additions_have_human_labels():
+    labels = {model["id"]: model["label"] for model in _opencode_go_static_models()}
+    assert labels["gpt-5.6-luna"] == "GPT 5.6 Luna"
+    assert labels["kimi-k3"] == "Kimi K3"
+    assert labels["glm-5.3"] == "GLM-5.3"
+    assert labels["grok-4.5"] == "Grok 4.5"
+    assert labels["qwen3.8-max"] == "Qwen3.8 Max"
+    assert labels["muse-spark-1.2-contributor"] == "Muse Spark 1.2 Contributor"
+    assert labels["ox-alpha-free"] == "Ox Alpha (Go)"