Fix indentation in Mermaid sequence diagrams

Corrects the indentation of nested block structures (alt, opt, par,
loop) in all four Mermaid sequence diagrams. Content inside nested
blocks is now properly indented relative to the block keywords, making
the hierarchical structure clearer and more readable.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <[email protected]>

Author: jonathanhefner

specification/draft/apps.mdx

@@ -636,49 +636,49 @@ The typical lifecycle for rendering a UI resource:
 
 ```mermaid
 sequenceDiagram
- participant H as Host
- participant S as MCP Server
+  participant H as Host
+  participant S as MCP Server
 
- autonumber
-   S -->> H: resources/list (includes ui:// resources)
-   S -->> H: tools/list (includes tools with ui/resourceUri metadata)
+  autonumber
+  S -->> H: resources/list (includes ui:// resources)
+  S -->> H: tools/list (includes tools with ui/resourceUri metadata)
 ```
 
 #### 2. UI Initialization (Desktop/Native Hosts)
 
 ```mermaid
 sequenceDiagram
- participant H as Host
- participant UI as Guest UI (iframe)
- participant P as Sandbox Proxy
- participant S as MCP Server
-
- autonumber
- par UI Tool call
-   H ->> S: tools/call to Tool with ui/resourceUri metadata
- and UI initialization
-   alt Desktop/Native hosts
-   H ->> H: Render Guest UI in an iframe (HTML from the ui:// resource)
-   else Web hosts
-   H ->> H: Render Sandbox Proxy in an iframe (different origin)
-   P ->> H: ui/notifications/sandbox-ready
-   H -->> P: ui/notifications/sandbox-resource-ready (HTML content)
-   P -> P: Render inner iframe with HTML
-
-   end
-   UI ->> H: ui/initialize
-   H -->> UI: McpUiInitializeResult (e.g., host-context, capabilities, etc.)
-   UI ->> H: ui/notifications/initialized
-   opt Stream Tool input to UI
-     H -->> UI: ui/notifications/tool-input-partial (0..n)
-   end
-   H -->> UI: ui/notifications/tool-input (complete)
- end
- alt Tool complete
-   H -->> UI: ui/notifications/tool-result
- else Tool cancelled
-   H -->> UI: ui/notifications/tool-cancelled
- end
+  participant H as Host
+  participant UI as Guest UI (iframe)
+  participant P as Sandbox Proxy
+  participant S as MCP Server
+
+  autonumber
+  par UI Tool call
+    H ->> S: tools/call to Tool with ui/resourceUri metadata
+  and UI initialization
+    alt Desktop/Native hosts
+      H ->> H: Render Guest UI in an iframe (HTML from the ui:// resource)
+    else Web hosts
+      H ->> H: Render Sandbox Proxy in an iframe (different origin)
+      P ->> H: ui/notifications/sandbox-ready
+      H -->> P: ui/notifications/sandbox-resource-ready (HTML content)
+      P -> P: Render inner iframe with HTML
+
+    end
+    UI ->> H: ui/initialize
+    H -->> UI: McpUiInitializeResult (e.g., host-context, capabilities, etc.)
+    UI ->> H: ui/notifications/initialized
+    opt Stream Tool input to UI
+      H -->> UI: ui/notifications/tool-input-partial (0..n)
+    end
+    H -->> UI: ui/notifications/tool-input (complete)
+  end
+  alt Tool complete
+    H -->> UI: ui/notifications/tool-result
+  else Tool cancelled
+    H -->> UI: ui/notifications/tool-cancelled
+  end
 ```
 
 Note: when the Guest UI is rendered inside a sandbox, the sandbox transparently passes messages between the Guest UI and the Host, except for messages named `ui/notifications/sandbox-*`.
@@ -687,51 +687,51 @@ Note: when the Guest UI is rendered inside a sandbox, the sandbox transparently
 
 ```mermaid
 sequenceDiagram
- actor U as User / Agent
- participant H as Host
- participant UI as Guest UI (iframe)
- participant S as MCP Server
- loop Interactive phase
-   U ->> UI: interaction (e.g., click)
-   alt Tool call
-     UI ->> H: tools/call
-     H ->> S: tools/call
-     opt Stream Tool input to UI
-       H -->> UI: ui/notifications/tool-input-partial (0..n)
-     end
-     H -->> UI: ui/notifications/tool-input (complete)
-     H-->>UI: ui/notifications/tool-result
- else Message
-   UI ->> H: ui/message
-   H -->> H: Process message and follow up
- else Notify
-     UI ->> H: notifications/message
-     H ->> H: Process notification and store in context
- else Resource read
-     UI ->> H: resources/read
-     H ->> S: resources/read
-     S --> H: resources/read response
-     H --> UI: resources/read response
-   end
-   opt UI notifications
-     UI ->> H: notifications (e.g., ui/notifications/size-change)
-   end
-   opt Host notifications
-     H ->> UI: notifications (e.g., ui/notifications/host-context-change)
-   end
- end
+  actor U as User / Agent
+  participant H as Host
+  participant UI as Guest UI (iframe)
+  participant S as MCP Server
+  loop Interactive phase
+    U ->> UI: interaction (e.g., click)
+    alt Tool call
+      UI ->> H: tools/call
+      H ->> S: tools/call
+      opt Stream Tool input to UI
+        H -->> UI: ui/notifications/tool-input-partial (0..n)
+      end
+      H -->> UI: ui/notifications/tool-input (complete)
+      H-->>UI: ui/notifications/tool-result
+    else Message
+      UI ->> H: ui/message
+      H -->> H: Process message and follow up
+    else Notify
+      UI ->> H: notifications/message
+      H ->> H: Process notification and store in context
+    else Resource read
+      UI ->> H: resources/read
+      H ->> S: resources/read
+      S --> H: resources/read response
+      H --> UI: resources/read response
+    end
+    opt UI notifications
+      UI ->> H: notifications (e.g., ui/notifications/size-change)
+    end
+    opt Host notifications
+      H ->> UI: notifications (e.g., ui/notifications/host-context-change)
+    end
+  end
 ```
 
 #### 6. Cleanup
 
 ```mermaid
 sequenceDiagram
- participant H as Host
- participant UI as Guest UI (iframe)
- H ->> UI: ui/resource-teardown
- UI --> UI: Graceful termination
- UI -->> H: ui/resource-teardown response
- H -x H: Tear down iframe and listeners
+  participant H as Host
+  participant UI as Guest UI (iframe)
+  H ->> UI: ui/resource-teardown
+  UI --> UI: Graceful termination
+  UI -->> H: ui/resource-teardown response
+  H -x H: Tear down iframe and listeners
 ```
 
 Note: Cleanup may be triggered at any point in the lifecycle following UI initialization.