stacks(char-rp): compose-ify the two NVFP4 RP seats (MeroMero + Dark-Scarlett)

Replaces the ad-hoc docker-run seats with proper compose stacks on ana-ml2, mirrored here:
- meromero-charrp: G4-MeroMero-v2-31B NVFP4A16, char-rp prose (non-thinking, multimodal,
  vision-enabled), GPU0, 256K @ ~2x. util 0.52 (leaves ~4.6GB GPU0 headroom).
- darkscarlett-charrp-reasoning: Dark-Scarlett-v1.0-27B NVFP4A16 (Qwen wrapper recipe),
  char-rp-reasoning thinking seat, GPU1, 256K. MTP deferred (no spec-decode).
Both survive reboot now. Supersede the retired char-rp-gguf + heretic2-charrp-reasoning stacks.

stacks/meromero-charrp/README.md

@@ -0,0 +1,20 @@
+# meromero-charrp — MeroMero-v2 char-rp prose seat (ana-ml2 GPU0)
+
+The **non-thinking, multimodal** RP prose seat. Serves the LiteLLM `char-rp` alias.
+
+- **Model:** `G4-MeroMero-v2-31B-NVFP4A16` (Gemma-4-31B, home-quantized weight-only NVFP4A16).
+- **Host/GPU:** ana-ml2, GPU0 (co-located with `gen` / vllm-aeon-gen).
+- **Port:** :8016 → LiteLLM `char-rp`.
+- **Context:** 256K (`--max-model-len 262144`). Gemma-4 uses sliding-window attention → KV-efficient, ~2× concurrency at full context.
+- **Vision:** enabled (image + text). `preprocessor_config.json` was materialized from the model's own `processor_config.json` (`Gemma4ImageProcessor`); audio is config-declared but weightless.
+- **Tuning:** `.env` — `MEROMERO_GPU_MEM_UTIL=0.52` (leaves ~4.6 GB GPU0 headroom), `MEROMERO_MAX_MODEL_LEN=262144`, `MEROMERO_GPU_ID=0`.
+
+Replaces the retired **char-rp-gguf** (Magidonia-24B GGUF / llama.cpp) seat. The quant pipeline
+lives in `ana-ml2:/tank/aimodels/meromero-v2-nvfp4-work/`.
+
+## Deploy
+
+```bash
+scripts/deploy-stack.sh ana-ml2 meromero-charrp     # diffs vs live, prompts y/N
+# on host: cp .env.example .env; docker compose up -d
+```