Support recursive annotated and staged types

[CraigMacomber]

Description

Add support for recursive annotated and staged types.

Reviewer Guidance

The review process is outlined on this wiki page.

[Copilot]

Pull Request Overview

This PR adds support for recursive annotated and staged types to the schema system. The changes introduce new "unsafe" type utilities and recursive variants of existing APIs that can handle recursive type definitions where the standard TypeScript type system has limitations.

Key changes:

• Adds new *Unsafe type variants that use Unenforced constraints to work around TypeScript recursion limitations
• Introduces stagedRecursive and typesRecursive methods to SchemaFactoryAlpha for handling recursive schema definitions
• Provides comprehensive test coverage for the new recursive type APIs

Reviewed Changes

Copilot reviewed 12 out of 12 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
packages/framework/fluid-framework/api-report/fluid-framework.alpha.api.md	Adds API surface for new unsafe type utilities and recursive methods
packages/dds/tree/api-report/tree.alpha.api.md	Mirrors the API changes for the tree package
packages/dds/tree/src/simple-tree/api/typesUnsafe.ts	Implements core unsafe type utilities for recursive schema support
packages/dds/tree/src/simple-tree/api/schemaFactoryAlpha.ts	Adds stagedRecursive and typesRecursive methods to SchemaFactoryAlpha
packages/dds/tree/src/simple-tree/api/schemaStatics.ts	Documents the unsafe field schema creation utility
packages/dds/tree/src/test/simple-tree/core/allowedTypes.spec.ts	Adds test coverage for type annotation utilities
packages/dds/tree/src/test/simple-tree/api/typesUnsafe.spec.ts	Tests the new unsafe type utilities
packages/dds/tree/src/test/simple-tree/api/schemaStatics.spec.ts	Tests schema statics functionality
packages/dds/tree/src/test/simple-tree/api/schemaFactoryRecursive.spec.ts	Comprehensive test suite for recursive schema features
Multiple index files	Export the new unsafe types and utilities

[CraigMacomber]

Here is the main test suit for the new APIs: rest of the test changes are mostly incidental from a lot of experiments, but worth keeping.

[jenn-le]

Is this something we want to do or just a note for later? feels like it'll be easily lost

[CraigMacomber]

This is just a note for if someone comes to fiddle with this APi in the future to try and make it more type safe to save them a couple hours of experimenting that I already did.

[github-actions]

🔗 Found some broken links! 💔

Run a link check locally to find them. See
https://github.com/microsoft/FluidFramework/wiki/Checking-for-broken-links-in-the-documentation for more information.

linkcheck output

> fluid-framework-docs-site@0.0.0 ci:check-links /home/runner/work/FluidFramework/FluidFramework/docs
> start-server-and-test "npm run serve -- --no-open" 3000 check-links

1: starting server using command "npm run serve -- --no-open"
and when url "[ 'http://127.0.0.1:3000' ]" is responding with HTTP status code 200
running tests using command "npm run check-links"


> fluid-framework-docs-site@0.0.0 serve
> docusaurus serve --no-open

[SUCCESS] Serving "build" directory at: http://localhost:3000/

> fluid-framework-docs-site@0.0.0 check-links
> linkcheck http://localhost:3000 --skip-file skipped-urls.txt

 ELIFECYCLE  Command failed with exit code 1.

[alexvy86]

Approving for docs.