fix(skills/comfyui): bug fixes, cloud parity, expanded coverage, examples, tests

The audit of v4.1 surfaced ~70 issues across the five scripts and three
reference docs — most user-visible (silent file overwrites, status-error
misclassified as success, X-API-Key leaked to S3 on /api/view redirect,
Cloud endpoints that 404 because they were renamed). v5.0.0 fixes those
and fills the gaps that previously forced users to write their own glue
(WebSocket monitoring, batch/sweep, img2img upload helper, dep auto-fix,
log fetch, health check, example workflows).

Critical fixes
- run_workflow.py: poll_status now checks status_str==error BEFORE
  completed:true, so a failed run no longer reports success
- run_workflow.py: download_output streams to disk via safe_path_join,
  preserves server subfolder structure (no silent overwrites), and
  retries with exponential backoff
- run_workflow.py: refuses to overwrite a link with a literal in
  inject_params (would silently break wiring)
- _common.py: _StripSensitiveOnRedirectSession (subclasses
  requests.Session.rebuild_auth) drops X-API-Key/Cookie on cross-host
  redirects — fixes a real key-leak path through Cloud's signed-URL
  download flow. Tested
- Cloud routing (verified live): /history → /history_v2,
  /models/<f> → /experiment/models/<f>, plus folder aliases for the
  unet ↔ diffusion_models and clip ↔ text_encoders rename
- check_deps.py: distinguishes 200/empty vs 404 folder_not_found vs
  403 free-tier; emits concrete fix_command per missing dep
- extract_schema.py: prompt vs negative_prompt determined by tracing
  KSampler.{positive,negative} connections (incl. through Reroute /
  Primitive nodes) instead of meta-title heuristic; symmetric
  duplicate-name resolution; cycle-safe trace_to_node
- hardware_check.py: multi-GPU pick-best, Apple variant detection,
  Rosetta detection, WSL2, ROCm --json, disk-space check, optional
  PyTorch probe; powershell preferred over deprecated wmic
- comfyui_setup.sh: prefers pipx → uvx → pip --user (with PEP-668
  fallback); idempotent — skips relaunch if server already up;
  configurable port/workspace; persistent log; SIGINT trap

New scripts
- run_batch.py — count or sweep (cartesian product), parallel up to
  cloud tier limit
- ws_monitor.py — real-time WebSocket viewer; saves preview frames
- auto_fix_deps.py — runs comfy node install / model download for
  whatever check_deps reports missing (with --dry-run)
- health_check.py — single command that runs the verification checklist
  (comfy-cli + server + checkpoints + optional smoke test that cancels
  itself to avoid burning compute)
- fetch_logs.py — pull traceback / status messages for a prompt_id

Coverage expansion
- Param patterns now cover Flux (BasicScheduler, BasicGuider,
  RandomNoise, ModelSamplingFlux), SD3, Wan/Hunyuan/LTX video,
  IPAdapter, rgthree, easy-use, AnimateDiff
- Embedding refs in CLIPTextEncode strings extracted as model deps
- ckpt_name / vae_name / lora_name / unet_name now controllable so
  workflows can be retargeted per run

Examples
- workflows/{sd15,sdxl,flux_dev}_txt2img.json
- workflows/sdxl_{img2img,inpaint}.json
- workflows/upscale_4x.json
- workflows/{animatediff_video,wan_video_t2v}.json + README

Tests
- 117 tests (105 unit + 8 cloud integration + 4 cross-host security)
- Cloud tests auto-skip without COMFY_CLOUD_API_KEY; verified end-to-end
  against live cloud API

Backwards compatibility
- All existing CLI flags continue to work; new behavior is opt-in
  (--ws, --input-image, --randomize-seed, --flat-output, etc.)

skills/creative/comfyui/tests/test_check_deps.py

@@ -0,0 +1,65 @@
+"""Tests for check_deps.py — focuses on parsing logic that doesn't need a server."""
+
+from __future__ import annotations
+
+from check_deps import (
+    NODE_TO_PACKAGE,
+    model_present,
+    normalize_for_match,
+    suggest_install_command,
+)
+
+
+class TestNormalizeForMatch:
+    def test_basic(self):
+        s = normalize_for_match("model.safetensors")
+        assert "model.safetensors" in s
+        assert "model" in s
+
+    def test_subfolder(self):
+        s = normalize_for_match("subdir/model.pt")
+        assert "subdir/model.pt" in s
+        assert "model.pt" in s
+        assert "model" in s
+
+
+class TestModelPresent:
+    def test_exact_match(self):
+        assert model_present("a.safetensors", {"a.safetensors", "b.safetensors"}) is True
+
+    def test_extension_difference(self):
+        # User said "model" but installed is "model.safetensors"
+        assert model_present("model", {"model.safetensors"}) is True
+        # Reverse direction — also matches
+        assert model_present("model.safetensors", {"model"}) is True
+
+    def test_subfolder_match(self):
+        # Installed list has "subdir/model.safetensors", workflow asks "model.safetensors"
+        assert model_present("model.safetensors", {"subdir/model.safetensors"}) is True
+
+    def test_missing(self):
+        assert model_present("missing.safetensors", {"a.safetensors", "b.safetensors"}) is False
+
+    def test_empty_installed(self):
+        assert model_present("anything.safetensors", set()) is False
+
+
+class TestSuggestInstallCommand:
+    def test_known_node(self):
+        cmd = suggest_install_command("VHS_VideoCombine")
+        assert cmd == "comfy node install comfyui-videohelpersuite"
+
+    def test_unknown_node(self):
+        assert suggest_install_command("SomeRandomNodeName123") is None
+
+
+class TestNodePackageMap:
+    def test_no_duplicates(self):
+        # Each node should map to exactly one package
+        keys = list(NODE_TO_PACKAGE.keys())
+        assert len(keys) == len(set(keys))
+
+    def test_all_lowercase_packages(self):
+        # Convention: package names are lowercase with hyphens/underscores
+        for pkg in NODE_TO_PACKAGE.values():
+            assert pkg.lower() == pkg, f"Package name should be lowercase: {pkg}"