MiniMax H3 on RunPod: install/download scripts, ComfyUI wiring, benchmark harness, research docs

- scripts/pod: weight downloads (workspace + tmpfs overflow for volume quota),
  extra_model_paths.yaml, headless ComfyUI launcher, test image generator,
  one-shot pod installer
- scripts/local: auto-reconnecting port forward for the ComfyUI panel
- bench: API-based harness for t2v/i2v/ref2v across durations, resolutions,
  and weight families; CSV/JSONL results
- docs: WEIGHTS.md (what's downloaded where), RESEARCH.md (ComfyUI guides,
  no-Comfy options via SGLang/vLLM/diffusers, concurrency model, serverless)

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

scripts/pod/download-weights-tmpfs.sh

@@ -0,0 +1,41 @@
+#!/bin/bash
+# Overflow download for the weight files that don't fit under the /workspace
+# network-volume quota (~100GB on the current pod). Puts them on tmpfs
+# (/dev/shm, 176GB on the B200 pod) — EPHEMERAL: lost on pod restart, so this
+# is for benchmarking sessions. Re-run after any pod restart.
+#
+#   tmux new -s downloads-shm -d 'bash /workspace/minimax-h3/download-weights-tmpfs.sh'
+#
+# ComfyUI sees this path via the minimax_shm section of extra_model_paths.yaml.
+set -uo pipefail
+
+REPO="Comfy-Org/MiniMax-H3"
+DEST="/dev/shm/minimax-h3-models"
+LOG="/workspace/minimax-h3/download.log"
+
+mkdir -p "$DEST/diffusion_models"
+export HF_HUB_ENABLE_HF_TRANSFER=1
+
+log() { echo "[$(date -u +%FT%TZ)] $*" | tee -a "$LOG"; }
+
+dl() {
+  local file="$1"
+  if [ -f "$DEST/$file" ]; then
+    log "SKIP $file (already present in shm)"
+    return 0
+  fi
+  log "START $file -> tmpfs"
+  if hf download "$REPO" "$file" --local-dir "$DEST" >>"$LOG" 2>&1; then
+    log "DONE $file ($(du -h "$DEST/$file" | cut -f1))"
+  else
+    log "FAILED $file"
+    return 1
+  fi
+}
+
+log "=== tmpfs overflow download starting ==="
+dl diffusion_models/minimax_h3_fl2va_int8_convrot.safetensors
+dl diffusion_models/minimax_h3_ref2va_bf16.safetensors
+dl diffusion_models/minimax_h3_fl2va_bf16.safetensors
+rm -rf "$DEST/.cache"
+log "=== tmpfs overflow downloads complete ==="