docs(plugins): overhaul SDK pages with Mintlify components and IA restructure

- Rewrite building-plugins.md as focused quick-start with CardGroup routing
- Rewrite sdk-channel-plugins.md with Steps, CodeGroup, Accordion walkthrough
- Move SDK Migration under Building Plugins nav, rename to "Migrate to SDK"
- Fix code examples and use valid Lucide icons for Mintlify Cards

docs/docs.json

@@ -1044,7 +1044,8 @@
                     "pages": [
                       "plugins/building-plugins",
                       "plugins/sdk-channel-plugins",
-                      "plugins/sdk-provider-plugins"
+                      "plugins/sdk-provider-plugins",
+                      "plugins/sdk-migration"
                     ]
                   },
                   {
@@ -1055,7 +1056,6 @@
                       "plugins/sdk-runtime",
                       "plugins/sdk-setup",
                       "plugins/sdk-testing",
-                      "plugins/sdk-migration",
                       "plugins/manifest",
                       "plugins/architecture"
                     ]

docs/plugins/building-plugins.md

@@ -25,10 +25,10 @@ and users install with `openclaw plugins install <npm-spec>`.
 ## What kind of plugin?
 
 <CardGroup cols={3}>
-  <Card title="Channel plugin" icon="message" href="/plugins/sdk-channel-plugins">
+  <Card title="Channel plugin" icon="messages-square" href="/plugins/sdk-channel-plugins">
     Connect OpenClaw to a messaging platform (Discord, IRC, etc.)
   </Card>
-  <Card title="Provider plugin" icon="microchip" href="/plugins/sdk-provider-plugins">
+  <Card title="Provider plugin" icon="cpu" href="/plugins/sdk-provider-plugins">
     Add a model provider (LLM, proxy, or custom endpoint)
   </Card>
   <Card title="Tool / hook plugin" icon="wrench">
@@ -215,22 +215,22 @@ internal imports — never import your own plugin through its SDK path.
 ## Next steps
 
 <CardGroup cols={2}>
-  <Card title="Channel Plugins" icon="message" href="/plugins/sdk-channel-plugins">
+  <Card title="Channel Plugins" icon="messages-square" href="/plugins/sdk-channel-plugins">
     Build a messaging channel plugin
   </Card>
-  <Card title="Provider Plugins" icon="microchip" href="/plugins/sdk-provider-plugins">
+  <Card title="Provider Plugins" icon="cpu" href="/plugins/sdk-provider-plugins">
     Build a model provider plugin
   </Card>
-  <Card title="SDK Overview" icon="book" href="/plugins/sdk-overview">
+  <Card title="SDK Overview" icon="book-open" href="/plugins/sdk-overview">
     Import map and registration API reference
   </Card>
-  <Card title="Runtime Helpers" icon="gear" href="/plugins/sdk-runtime">
+  <Card title="Runtime Helpers" icon="settings" href="/plugins/sdk-runtime">
     TTS, search, subagent via api.runtime
   </Card>
-  <Card title="Testing" icon="flask" href="/plugins/sdk-testing">
+  <Card title="Testing" icon="test-tubes" href="/plugins/sdk-testing">
     Test utilities and patterns
   </Card>
-  <Card title="Plugin Manifest" icon="file-code" href="/plugins/manifest">
+  <Card title="Plugin Manifest" icon="file-json" href="/plugins/manifest">
     Full manifest schema reference
   </Card>
 </CardGroup>

docs/plugins/sdk-channel-plugins.md

@@ -348,16 +348,16 @@ extensions/acme-chat/
 ## Advanced topics
 
 <CardGroup cols={2}>
-  <Card title="Threading options" href="/plugins/sdk-entrypoints#registration-mode">
+  <Card title="Threading options" icon="git-branch" href="/plugins/sdk-entrypoints#registration-mode">
     Fixed, account-scoped, or custom reply modes
   </Card>
-  <Card title="Message tool integration" href="/plugins/architecture#channel-plugins-and-the-shared-message-tool">
+  <Card title="Message tool integration" icon="puzzle" href="/plugins/architecture#channel-plugins-and-the-shared-message-tool">
     describeMessageTool and action discovery
   </Card>
-  <Card title="Target resolution" href="/plugins/architecture#channel-target-resolution">
+  <Card title="Target resolution" icon="crosshair" href="/plugins/architecture#channel-target-resolution">
     inferTargetChatType, looksLikeId, resolveTarget
   </Card>
-  <Card title="Runtime helpers" href="/plugins/sdk-runtime">
+  <Card title="Runtime helpers" icon="settings" href="/plugins/sdk-runtime">
     TTS, STT, media, subagent via api.runtime
   </Card>
 </CardGroup>

docs/plugins/sdk-migration.md

@@ -1,6 +1,6 @@
 ---
 title: "Plugin SDK Migration"
-sidebarTitle: "SDK Migration"
+sidebarTitle: "Migrate to SDK"
 summary: "Migrate from the legacy backwards-compatibility layer to the modern plugin SDK"
 read_when:
   - You see the OPENCLAW_PLUGIN_SDK_COMPAT_DEPRECATED warning