litellm: wire GLM 5.2 (glm-5.2 + glm-5.2-reasoning) via z.ai passthrough

GLM 5.2 released ~2026-06; confirmed reachable with our existing
Z_AI_API_KEY (z.ai /models lists glm-5.2; a live completion returned
clean). Added two model_list entries mirroring the glm-5.1 pattern:
glm-5.2 (thinking DISABLED by default, per the 2026-06-11 operator call)
and glm-5.2-reasoning (thinking ENABLED, opt-in). Deployed to
ana-docker /opt/docker/conf/litellm/config.yaml, litellm restarted,
both verified through the gateway (disabled -> reasoning_tokens 0;
reasoning -> 234).

stacks/litellm/conf/config.yaml

@@ -151,6 +151,26 @@ model_list:
       extra_body:
         thinking:
           type: enabled
+  # glm-5.2 (released ~2026-06; canonical z.ai id `glm-5.2`, confirmed via /models +
+  #   a live completion with our key). Mirrors the glm-5.1 pattern: thinking DISABLED
+  #   by default (consistency with the 2026-06-11 operator call), opt-in reasoning via
+  #   glm-5.2-reasoning. extra_body.thinking is forwarded verbatim to z.ai.
+  - model_name: glm-5.2
+    litellm_params:
+      model: openai/glm-5.2
+      api_base: https://api.z.ai/api/coding/paas/v4
+      api_key: os.environ/Z_AI_API_KEY
+      extra_body:
+        thinking:
+          type: disabled
+  - model_name: glm-5.2-reasoning
+    litellm_params:
+      model: openai/glm-5.2
+      api_base: https://api.z.ai/api/coding/paas/v4
+      api_key: os.environ/Z_AI_API_KEY
+      extra_body:
+        thinking:
+          type: enabled
   - model_name: glm-5-turbo
     litellm_params:
       model: openai/glm-5-turbo