docs(SDK): Change location of convo-custom-visualizer

[VascoSch92]

• I have read and reviewed the documentation changes to the best of my ability.
• If the change is significant, I have run the documentation site locally and confirmed it renders as expected.

Summary of changes

The PR changes the location of the page convo-custom-visualizer as explained in issue #285

[openhands-ai]

Looks like there are a few issues preventing this PR from being merged!

• GitHub Actions are failing:
  • .github/workflows/sync-docs-code-blocks.yml
  • .github/workflows/sync-agent-sdk-openapi.yml

If you'd like me to help, just leave a comment, like

@OpenHands please fix the failing actions on PR #304 at branch `issue-285`

Feel free to include any additional details that might help me get this PR into a better state.

_{^{You can manage your notification settings}}

[VascoSch92]

Looks like there are a few issues preventing this PR from being merged!

* GitHub Actions are failing:
  
  * .github/workflows/sync-docs-code-blocks.yml
  * .github/workflows/sync-agent-sdk-openapi.yml

If you'd like me to help, just leave a comment, like

@OpenHands please fix the failing actions on PR #304 at branch `issue-285`

Feel free to include any additional details that might help me get this PR into a better state.

You can manage your notification settings

this is not true :-(