docs scanner: extensions issues (#25119)

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## Description

Closes #25077
Closes #25076
Closes #25078

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## Related issues or tickets

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## Reviews

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- [ ] Technical review
- [ ] Editorial review
- [ ] Product review

Author: aevesdocker

content/manuals/extensions/extensions-sdk/dev/api/backend.md

@@ -20,7 +20,7 @@ ddClient.extension.vm.service
  .then((value: any) => console.log(value)
 ```
 
-See [Service API Reference](/reference/api/extensions-sdk/HttpService.md) for other methods such as POST, UPDATE, and DELETE.
+See [Service API Reference](/reference/api/extensions-sdk/HttpService.md) for other HTTP methods.
 
 > Deprecated extension backend communication
 >

content/manuals/extensions/extensions-sdk/dev/api/dashboard.md

@@ -84,7 +84,7 @@ ddClient.host.openExternal("https://docker.com");
 
 For more details about method parameters and the return types available, see [Desktop host API reference](/reference/api/extensions-sdk/Host.md).
 
-> Deprecated user notifications
+> Deprecated external URL opening
 >
 > This method is deprecated and will be removed in a future version. Use the methods specified above.
 

content/manuals/extensions/extensions-sdk/dev/api/overview.md

@@ -34,4 +34,4 @@ The `ddClient` object gives access to various APIs:
 - [Dashboard](dashboard.md)
 - [Navigation](dashboard-routes-navigation.md)
 
-See also the [Extensions API reference](reference/api/extensions-sdk/_index.md).
+See also the [Extensions API reference](/reference/api/extensions-sdk/_index.md).