vLLM serving: patched deepseek_v4.py, disabled mega_moe, updated docs

- Add patches/deepseek_v4.py: patched vllm source file with modelopt NVFP4
  weight name mappings (expert gate_proj→w1, mlp→ffn, self_attn→attn.mla_attn,
  compressor.kv_proj→wkv, etc.), E2M1 FP4→BF16 unpacking for stacked params,
  skip patterns for NVFP4 scale tensors on MergedColumnParallelLinear, and
  resilient loading for unknown params.

- Update docker-compose.yml: copy patched deepseek_v4.py over original at
  container startup, remove --moe-backend=deep_gemm_mega_moe (no NVFP4 kernel).

- Update patches/patch_vllm_weights.py: legacy runtime monkey-patch approach
  (doesn't work with worker processes), kept for reference.

- Update README.md: added vLLM serving run history table (S1-S10), documented
  all open issues (MergedColumnParallelLinear+NVFP4, no mega_moe kernel,
  resilient loading), added vLLM-specific bug list and key notes.

- Update scripts/serve_vllm.py: add WARN comment on mega_moe flag.

scripts/serve_vllm.py

@@ -82,7 +82,7 @@ cmd = [
     "--tensor-parallel-size", "8",
     "--compilation-config", '{"cudagraph_mode":"FULL_AND_PIECEWISE", "custom_ops":["all"]}',
     "--attention_config.use_fp4_indexer_cache=True",
-    "--moe-backend", "deep_gemm_mega_moe",
+    "--moe-backend", "deep_gemm_mega_moe",  # WARN: No NVFP4 mega_moe kernel. Use docker-compose (omits this flag) instead.
     "--tokenizer-mode", "deepseek_v4",
     "--tool-call-parser", "deepseek_v4",
     "--enable-auto-tool-choice",