fix(cyberprev-seat): serve coherent v2 quant from name-repaired source; wire gateway

The first cyberprev quant served pure gibberish despite passing every structural
check. Root cause: the hotdogs/Qwen3.8-27B-abliterated-cyber-preview checkpoint
ships broken -- 850 of 1199 tensors (the whole transformer body) carry a TRIPLED
`language_model.` prefix, confirmed present in the upstream HF index (an unsloth
export bug, not our download). transformers silently loaded the unmapped tensors
as random-init, the pipeline quantized noise, and structural verification passed
because it inspects the output config, never that input names mapped. A plain
greedy coherence smoke caught it; nothing structural could.

Fix: rewrite tensor names against a known-good reference of the same architecture
(qwen38-27b-uncensored-bf16), verified the repaired name-set == reference name-set
exactly (1199 tensors, 0 collisions), and re-quantized from the corrected source
(cyberprev-bf16-fixed). v2 is coherence-verified (spec off AND live with dflash):
Paris/Berlin/Rome, correct arithmetic precedence, primes, clean cyber-domain chat
with a proper thinking split. dflash k=7 measured at 2.77 mean acceptance length.

Seat serves cyberprev-27b / cyberprev-27b-thinking on :8025/GPU0 with dflash k=7,
displacing the retired sentinel-r3. Gateway: removed the retired sentinel-r3 /
sentinel-r3-reasoning aliases and added cyberprev-27b / cyberprev-reasoning -- NOT
repointed, since serving cyberprev weights under sentinel's name is silent
substitution. Verified end-to-end through the gateway; sentinel-r3 now 400s.

Playbook gains a superseded-claims row: structural verification does not imply a
good quant; a coherence smoke is the load-bearing gate, and third-party sources
must have their tensor names diffed against a reference before quantizing.

Broken v1 quant dir removed.

stacks/litellm/conf/config.yaml

@@ -969,6 +969,44 @@ model_list:
     model_info:
       mode: chat
 
+  # cyberprev-27b -> hotdogs/Qwen3.8-27B-abliterated-cyber-preview (:8025, fv-ml1 GPU0).
+  # In-house mixed NVFP4 quant, dflash k=7. Replaced the retired sentinel-r3 seat 2026-09-14.
+  # Sampler mirrors sec/sec-reasoning so an A/B isolates weights, not sampling. The retired
+  # sentinel-r3 aliases were DELETED, not repointed — cyberprev weights under sentinel's name
+  # would be silent substitution.
+  - model_name: cyberprev-27b
+    litellm_params:
+      model: hosted_vllm/cyberprev-27b
+      api_base: http://10.251.50.54:8025/v1
+      api_key: os.environ/VLLM_API_KEY
+      temperature: 0.7
+      top_p: 0.8
+      presence_penalty: 0.0
+      extra_body:
+        top_k: 20
+        min_p: 0.0
+        repetition_penalty: 1.0
+        chat_template_kwargs:
+          enable_thinking: false
+    model_info:
+      mode: chat
+  - model_name: cyberprev-reasoning
+    litellm_params:
+      model: hosted_vllm/cyberprev-27b-thinking
+      api_base: http://10.251.50.54:8025/v1
+      api_key: os.environ/VLLM_API_KEY
+      temperature: 1.0
+      top_p: 0.95
+      presence_penalty: 0.0
+      extra_body:
+        top_k: 20
+        min_p: 0.0
+        repetition_penalty: 1.0
+        chat_template_kwargs:
+          enable_thinking: true
+    model_info:
+      mode: chat
+
 general_settings:
   master_key: os.environ/LITELLM_MASTER_KEY
   database_url: os.environ/DATABASE_URL