[ENG-927] Node tags documentation (#535)

* first commit

* finished documentation

Author: trangdoan982

apps/website/app/(docs)/docs/obsidian/navigation.ts

@@ -59,6 +59,10 @@ export const navigation: NavigationList = [
         title: "Canvas",
         href: `${ROOT}/canvas`,
       },
+      {
+        title: "Node tags",
+        href: `${ROOT}/node-tags`,
+      },
     ],
   },
 

apps/website/app/(docs)/docs/obsidian/pages/node-tags.md

@@ -0,0 +1,66 @@
+---
+title: "Node tags"
+date: "2025-10-15"
+author: ""
+published: true
+---
+
+## Overview
+
+Node tags allow you to quickly create discourse nodes from tagged lines in your notes. When you assign a tag to a node type, any line containing that tag becomes a clickable element that can be converted into a discourse node.
+
+This feature streamlines your workflow by letting you mark potential discourse nodes with tags as you write, then easily convert them to full discourse nodes later.
+
+## Setting up node tags
+
+### Configuring tags in settings
+
+1. Open the Discourse Graph settings
+2. Navigate to the **Node Types** section
+3. Select an existing node type or create a new one
+4. In the **Node tag** field, enter a tag identifier
+
+![Node tags setting](/docs/obsidian/node-tags-setting.png)
+
+### Tag naming rules
+
+Tags must follow these rules:
+- **No spaces**: Tags cannot contain whitespace
+- **Allowed characters**: Only letters (a-z, A-Z), numbers (0-9), and dashes (-)
+- **No special characters**: Characters like #, @, /, \, etc. are not allowed
+- **Case-sensitive**: Tags are case-sensitive in the editor
+
+#### Tag examples
+
+**Valid tags:**
+- `clm-candidate`
+- `question-idea`
+- `evidence2024`
+- `my-argument`
+
+**Invalid tags:**
+- `clm candidate` (contains space)
+- `#clm-candidate` (contains #)
+- `clm/candidate` (contains /)
+
+## Using node tags in your notes
+
+### Adding tags to your notes
+
+Once you've configured a node tag for a node type, simply add the tag (prefixed with `#`) to any line in your notes:
+
+![Node tags example](/docs/obsidian/node-tags-example.png)
+
+### Creating discourse nodes from tags
+
+When you hover over a tagged line, a button appears above the tag:
+
+1. **Hover** over the tag you want to convert
+2. Wait for the **"Create [Node Type]"** button to appear
+![On hover](/docs/obsidian/on-hover-node-tag.png)
+3. **Click** the button to open the node creation dialog
+![Node creation dialog](/docs/obsidian/create-node-dialog-node-tag.png)
+4. Click "Confirm" to create node
+
+You'll see that the candidate node is now replaced with a formalized node
+![node created from tag](/docs/obsidian/node-tag-created.png)