feat(litellm): wire char-rp-reasoning + char-rp-fable to the Fable-Fusion seat

Operator-directed evaluation window. char-rp-reasoning now resolves to
Fable-Fusion 711 on :8019 instead of Dark-Scarlett on :8018; DS is DOWN
because GPU1 is zero-sum and FF occupies her slot.

This is an EXPLICIT substitution, not a silent alias swap: the config
block says so in place, carries the measured justification, and names the
rollback. char-rp-fable is added as the seat's honest name so the
evaluation can address it without depending on the temporary repoint, and
as a distinct model_name it gets its own litellm_params object rather than
sharing one (which is what bleeds sampler overrides between variants).

Samplers are unchanged from the DS entry and match the model card's
thinking-mode recommendation (temp 1.0 / top_p 0.95 / top_k 20). Verified
the FF chat template actually honours enable_thinking
(chat_template.jinja:44) rather than ignoring it -- the mismatch that
returned null content on the MeroMero seat.

Verified end-to-end through the gateway on both aliases: prose in content,
CoT in reasoning_content, finish=stop.

CONSUMER HAZARD: FF reasons heavily (2.1-4.6k chars). At max_tokens=1200
one of seven calls returned EMPTY content with finish_reason=length --
reasoning ate the whole budget. Not a refusal and not an alias fault. Use
max_tokens >= 3072; 6/6 clean there. No default is baked into the alias
because that would override caller intent silently.

stacks/litellm/conf/config.yaml

@@ -194,10 +194,52 @@ model_list:
   #   NO presence/rep penalty; DRY 0.8 server-side). Tuning ladder: flat prose→min_p 0.08, loops→DRY 0.9,
   #   over-damped→DRY 0.6/off. Do NOT import RpR/QwQ sampler rules (different family). NOT the same model as
   #   char-rp (best-of-breed per seat) — see stacks/char-rp-gguf/README.md.
+  # ⚠️ TEMPORARY REPOINT 2026-08-16 (operator-directed evaluation window).
+  #   char-rp-reasoning currently resolves to FABLE-FUSION 711 on :8019, NOT to
+  #   Dark-Scarlett. DS v1.0 is DOWN — GPU1 is zero-sum and Fable-Fusion occupies
+  #   her slot. This is a deliberate, explicit substitution for hands-on testing;
+  #   it is NOT a silent alias swap, and it is not the permanent seat decision.
+  #   Address the seat unambiguously as `char-rp-fable` below; `char-rp-reasoning`
+  #   is kept live only so existing consumers keep working during the window.
+  #
+  #   WHY: DS v1.0 is a plain finetune of stock Qwen3.6-27B with NO abliteration,
+  #   so cold prompts revert to safety-tuned base behaviour. Measured three-arm
+  #   A/B (services/refusal-probe/): under a bare instruction with no character
+  #   card, DS refuses 92.5% (37/40) and Fable-Fusion 15.8% (6/38); with a
+  #   character card both sit at ~0%. Fable-Fusion is Heretic-abliterated.
+  #
+  #   ROLLBACK (restores Dark-Scarlett):
+  #     ssh infra-ops@10.250.50.54 'cd /opt/docker/compose/fablefusion-charrp-probe && sudo docker compose down'
+  #     ssh infra-ops@10.250.50.54 'cd /opt/docker/compose/darkscarlett-charrp-reasoning && sudo docker compose up -d'
+  #     then revert this block to api_base :8018 / model hosted_vllm/char-rp-reasoning
+  #     and restart litellm (~52s).
+  #
+  #   Samplers below are the model card's thinking-mode recommendation (temp 1.0 /
+  #   top_p 0.95 / top_k 20) and are unchanged from the DS entry. Verified the FF
+  #   chat template honours `enable_thinking` (chat_template.jinja:44) rather than
+  #   ignoring it — the mismatch that returned null content on the MeroMero seat.
   - model_name: char-rp-reasoning
     litellm_params:
-      model: hosted_vllm/char-rp-reasoning
-      api_base: http://10.250.50.54:8018/v1
+      model: hosted_vllm/char-rp-probe
+      api_base: http://10.250.50.54:8019/v1
+      api_key: os.environ/VLLM_API_KEY
+      temperature: 1.0
+      top_p: 0.95
+      extra_body:
+        top_k: 20
+        chat_template_kwargs:
+          enable_thinking: true
+    model_info:
+      mode: chat
+  # char-rp-fable -> the SAME Fable-Fusion seat under its own honest name, so the
+  #   evaluation can address it without relying on the temporary repoint above.
+  #   Distinct model_name = distinct litellm_params object, which avoids the
+  #   shared-deployment param mutation that bleeds sampler overrides between
+  #   variants.
+  - model_name: char-rp-fable
+    litellm_params:
+      model: hosted_vllm/char-rp-probe
+      api_base: http://10.250.50.54:8019/v1
       api_key: os.environ/VLLM_API_KEY
       temperature: 1.0
       top_p: 0.95