docs issue: no 0.5 -> 0.6 update documentation for tools and functions

Check Existing Issues

[x] I have searched for any existing and/or related issues.
[x] I have searched for any existing and/or related discussions.
[x] I am using the latest version of Open WebUI.

Installation Method

Docker

Open WebUI Version

0.6.32

Ollama Version (if applicable)

No response

Operating System

ubuntu

Browser (if applicable)

No response

Confirmation

[x] I have read and followed all instructions in README.md.
[x] I am using the latest version of both Open WebUI and Ollama.
[x] I have included the browser console logs.
[x] I have included the Docker container logs.
[x] I have provided every relevant configuration, setting, and environment variable used in my setup.
[x] I have clearly listed every relevant configuration, custom setting, environment variable, and command-line option that influences my setup (such as Docker Compose overrides, .env values, browser settings, authentication configurations, etc).
[x] I have documented step-by-step reproduction instructions that are precise, sequential, and leave nothing to interpretation. My steps:
Start with the initial platform/version/OS and dependencies used,
Specify exact install/launch/configure commands,
List URLs visited, user input (incl. example values/emails/passwords if needed),
Describe all options and toggles enabled or changed,
Include any files or environmental changes,
Identify the expected and actual result at each stage,
Ensure any reasonably skilled user can follow and hit the same issue.

Expected Behavior

There should be an official migration guide for 0.5 → 0.6 in the documentation.

This guide should list:

All breaking changes between 0.5 and 0.6.

Deprecated imports, functions, and modules.

New replacements or updated usage examples.

Steps required to update custom tools, plugins, and extensions.

Actual Behavior

Currently, the official documentation includes a Migration Guide: 0.4 → 0.5, but there is no migration guide for 0.5 → 0.6. When upgrading to version 0.6.x, many tools, functions, and imports no longer work due to breaking changes in the API and plugin structure. Without documentation, it is unclear what needs to be modified to make custom tools and extensions compatible.