chore(login): migrate nextjs login to monorepo (#10134)

# Which Problems Are Solved

We move the login code to the zitadel repo.

# How the Problems Are Solved

The login repo is added to ./login as a git subtree pulled from the
dockerize-ci branch.
Apart from the login code, this PR contains the changes from #10116

# Additional Context

- Closes https://github.com/zitadel/typescript/issues/474
- Also merges #10116  
- Merging is blocked by failing check because of:
- https://github.com/zitadel/zitadel/pull/10134#issuecomment-3012086106

---------

Co-authored-by: Max Peintner <peintnerm@gmail.com>
Co-authored-by: Max Peintner <max@caos.ch>
Co-authored-by: Florian Forster <florian@zitadel.com>

LICENSING.md

@@ -18,6 +18,13 @@ The following files and directories, including their subdirectories, are license
 proto/
 ```
 
+
+The following files and directories, including their subdirectories, are licensed under the [MIT License](https://opensource.org/license/mit/):
+
+```
+login/
+```
+
 ## Community Contributions
 
 To maintain a clear licensing structure and facilitate community contributions, all contributions must be licensed under the [Apache License 2.0](https://www.apache.org/licenses/LICENSE-2.0) to be accepted. By submitting a contribution, you agree to this licensing.