Add default trusted types policy

[dannimad]

Adding a default Trusted Types policy to prevent warning messages in supported browsers, which were triggered by innerHTML usage in Docusaurus-generated output. Some content is still injected as plain strings even after adding webpack config. By adding a default policy that simply returns the original string, we suppress these warnings without affecting runtime behavior. This is safe because our content is static and known at build time.

[Copilot]

Pull Request Overview

This PR adds a default Trusted Types policy to suppress innerHTML warning messages in browsers, ensuring that static content injected from Docusaurus remains safe and warning-free.

• Added a new JavaScript file that creates a default Trusted Types policy
• Updated the Docusaurus configuration to load the new policy script

Reviewed Changes

Copilot reviewed 2 out of 3 changed files in this pull request and generated no comments.

File	Description
docs/static/trusted-types-policy.js	Introduces a policy that returns the input string unchanged
docs/docusaurus.config.ts	Adds script configuration to inject the Trusted Types policy

Files not reviewed (1)

• docs/static/staticwebapp.config.json: Language not supported

[Abe27342]

ok with this as a stepping stone/confirmation that trusted types can be configured this way in our build system. Before closing out the item though IMO we need something a bit stricter.

[github-actions]

🔗 No broken links found! ✅

Your attention to detail is admirable.

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

Crawling...

Stats:
  164989 links
    1316 destination URLs
    1547 URLs ignored
       0 warnings
       0 errors