Update README and architecture diagram for v2.1.0

Add SaveSnapshot node to features list and architecture diagram,
update storage label from IndexedDB to Server Storage, add
maxNodeSnapshots setting to the table, and document the
node-triggered capture flow.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

README.md

@@ -5,7 +5,7 @@
 <p align="center">
   <a href="https://registry.comfy.org/publishers/ethanfel/nodes/comfyui-snapshot-manager"><img src="https://img.shields.io/badge/ComfyUI-Registry-blue?logo=data:image/svg%2bxml;base64,PHN2ZyB4bWxucz0iaHR0cDovL3d3dy53My5vcmcvMjAwMC9zdmciIHZpZXdCb3g9IjAgMCAyNCAyNCI+PHBhdGggZD0iTTEyIDJMMyA3djEwbDkgNSA5LTVWN2wtOS01eiIgZmlsbD0id2hpdGUiLz48L3N2Zz4=" alt="ComfyUI Registry"/></a>
   <a href="LICENSE"><img src="https://img.shields.io/badge/license-MIT-green" alt="MIT License"/></a>
-  <img src="https://img.shields.io/badge/version-2.0.0-blue" alt="Version"/>
+  <img src="https://img.shields.io/badge/version-2.1.0-blue" alt="Version"/>
   <img src="https://img.shields.io/badge/ComfyUI-Extension-purple" alt="ComfyUI Extension"/>
 </p>
 
@@ -27,6 +27,7 @@
 - **Per-workflow storage** — Each workflow has its own independent snapshot history
 - **Theme-aware UI** — Adapts to light and dark ComfyUI themes
 - **Toast notifications** — Visual feedback for save, restore, and error operations
+- **SaveSnapshot node** — Trigger snapshot captures from your workflow with a custom node; node snapshots are visually distinct (purple border + "Node" badge) and have their own rolling limit
 - **Lock/pin snapshots** — Protect important snapshots from auto-pruning and "Clear All" with a single click
 - **Concurrency-safe** — Lock guard prevents double-click issues during restore
 - **Server-side storage** — Snapshots persist on the ComfyUI server's filesystem, accessible from any browser
@@ -105,6 +106,7 @@ All settings are available in **ComfyUI Settings > Snapshot Manager > Capture Se
 | **Capture delay** | Slider | `3s` | Seconds to wait after the last edit before auto-capturing (1–30s) |
 | **Max snapshots per workflow** | Slider | `50` | Maximum number of unlocked snapshots kept per workflow (5–200). Oldest unlocked are pruned automatically; locked snapshots are never pruned |
 | **Capture on workflow load** | Toggle | `On` | Save an "Initial" snapshot when a workflow is first loaded |
+| **Max node-triggered snapshots** | Slider | `5` | Rolling limit for SaveSnapshot node captures per workflow (1–50). Node snapshots are pruned independently from auto/manual snapshots |
 
 ## Architecture
 
@@ -112,7 +114,7 @@ All settings are available in **ComfyUI Settings > Snapshot Manager > Capture Se
   <img src="assets/architecture.png" alt="Architecture Diagram" width="100%"/>
 </p>
 
-**Data flow:**
+**Auto/manual capture flow:**
 
 1. **Graph edits** trigger a `graphChanged` event
 2. A **debounce timer** prevents excessive writes
@@ -121,6 +123,13 @@ All settings are available in **ComfyUI Settings > Snapshot Manager > Capture Se
 5. The **sidebar panel** fetches snapshots from the server and renders the snapshot list
 6. **Restore/Swap** loads graph data back into ComfyUI with a lock guard to prevent concurrent operations
 
+**Node-triggered capture flow:**
+
+1. **SaveSnapshot node** executes during a queue prompt run
+2. A **WebSocket event** is sent to the frontend, **skipping hash dedup** (the workflow doesn't change between runs)
+3. The snapshot is saved with `source: "node"` and pruned against its own rolling limit (`maxNodeSnapshots`)
+4. Node snapshots appear in the sidebar with a **purple left border** and **"Node" badge**
+
 **Storage:** Snapshots are stored as JSON files on the server at `<extension_dir>/data/snapshots/<workflow_key>/<id>.json`. They persist across browser sessions, ComfyUI restarts, and are accessible from any browser connecting to the same server.
 
 ## FAQ