[material_ui] Add all M3 templates and generated code to `temporarily_excluded/` before migration (#12661)

Work towards https://github.com/flutter/flutter/issues/191088

**Ports over https://github.com/flutter/packages/pull/12206 which landed on the `m3e_migration` feature branch.**

### Original PR description

Work towards https://github.com/flutter/flutter/issues/187899

Moves all M3 templates and their generated code to gen_defaults/temporarily_excluded before we begin migrating.

This way when we migrate each component, we can first move the template and its respective generated code into the new directories, edit the template, and re-generate the code. This will make it easier to review changes to the templates and validate the generated output.

## Pre-Review Checklist

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