Initial commit: tuned multi-model llama.cpp stack

- 5 models: SmolLM3-3B, Gemma4-E2B/E4B, Qwen3-4B, Qwen3.5-9B
- TurboQuant image (FORCE_MMQ): +6-11% free speed on Turing GPUs
- Bigctx profiles (-nkvo KV in RAM): 2-16x context gain
- turbo2 KV: 2x smaller, benchmarked against PPL quality gate
- Per-model env files with justified parameters
- kv_quant_test.sh + cpu_ctx_test.sh benchmark scripts
- docs/FINDINGS.md: surprises, pitfalls, recommendations
- docs/ARCHITECTURE.md: compose + test script design

envs/.env.qwen35-9b

@@ -0,0 +1,41 @@
+# ==============================================================================
+# Qwen3.5-9B-Claude-4.6-Opus-Reasoning-Distilled-v2 Q8_0 — TurboQuant SM75
+# Architecture: 32 layers (8 full-attn + 24 linear-attn), GQA 4 KV heads
+# Model size: 8.86 GB  |  VRAM usage: ~3.4 GB (11 layers on GPU)
+# RAM usage: ~5.5 GB (21 layers pinned via mlock)
+#
+# Benchmark results (turbo2 KV, ngl=11, fa=1):
+#   t=1→0.86  t=2→1.62  t=3→2.25  t=4→2.94  t=5→3.56  t=6→4.38 ← best
+#   t=8→4.22  t=12→3.61  (hyperthreading hurts above 6)
+# Theoretical ceiling: ~5.1 t/s (45 GB/s RAM BW ÷ 8.86 GB model)
+# Achieved: 4.38 t/s = 86% efficiency
+#
+# Download:
+#   huggingface-cli download Jackrong/Qwen3.5-9B-Claude-4.6-Opus-Reasoning-Distilled-v2-GGUF \
+#     Qwen3.5-9B.Q8_0.gguf --local-dir ./models/
+# ==============================================================================
+
+MODEL_FILE=Qwen3.5-9B.Q8_0.gguf
+
+# GPU: 11 layers fit in 3.7 GB VRAM. ngl=12 causes OOM at ctx>2048.
+N_GPU_LAYERS=11
+
+# 32K context fits with turbo2 KV (~104 MiB overhead vs ~3.3 GB for f16)
+CTX_SIZE=32768
+
+# t=6 is optimal for i7-10750H (6 physical cores). t>6 uses HT which hurts.
+THREADS=6
+THREADS_BATCH=6
+
+BATCH_SIZE=512
+UBATCH_SIZE=128
+
+# turbo2: 2-bit KV cache, 6.4× smaller than f16. Requires TurboQuant image.
+CACHE_TYPE_K=turbo2
+CACHE_TYPE_V=turbo2
+
+PARALLEL=1
+
+# --no-mmap --mlock: pins entire model in RAM (prevents paging, avoids cold reads)
+# --flash-attn on: required with turbo2 KV (fa=0 + turbo2 has no speed benefit)
+EXTRA_ARGS=--flash-attn on --no-mmap --mlock