[Cache, Speed] Fix build warnings

[pedrosousa]

Summary

Fixes the following build warnings in Cache and Speed docs:

[WARN] [astro-expressive-code] Error while highlighting code block using language "JavaScript" in document "/home/runner/work/cloudflare-docs/cloudflare-docs/src/content/docs/cache/advanced-configuration/serve-tailored-content.mdx". The language could not be found. Using "txt" instead. Ensure that all required languages are either part of the bundle or custom languages provided in the "langs" config option.
[WARN] [astro-expressive-code] Error while highlighting code block using language "JavaScript" in document "/home/runner/work/cloudflare-docs/cloudflare-docs/src/content/docs/cache/advanced-configuration/serve-tailored-content.mdx". The language could not be found. Using "txt" instead. Ensure that all required languages are either part of the bundle or custom languages provided in the "langs" config option.
[WARN] [astro-expressive-code] Error while highlighting code block using language "JavaScript" in document "/home/runner/work/cloudflare-docs/cloudflare-docs/src/content/docs/cache/advanced-configuration/serve-tailored-content.mdx". The language could not be found. Using "txt" instead. Ensure that all required languages are either part of the bundle or custom languages provided in the "langs" config option.
[WARN] [vite] src/content/docs/speed/optimization/protocol/http2-to-origin.mdx (29:51): "Dashboard" is not exported by "src/components/index.ts", imported by "src/content/docs/speed/optimization/protocol/http2-to-origin.mdx".

[github-actions]

This pull request requires reviews from CODEOWNERS as it changes files that match the following patterns:

Pattern	Owners
/src/content/docs/cache/	@angelampcosta, @cloudflare/pcx-technical-writing
/src/content/docs/speed/	@angelampcosta, @cloudflare/pcx-technical-writing

[github-actions]

Preview URL: https://dccdb330.preview.developers.cloudflare.com
Preview Branch URL: https://pedro-2025-10-27-docs-fix-build-warnings.preview.developers.cloudflare.com

Files with changes (up to 15)

Original Link	Updated Link
https://developers.cloudflare.com/speed/optimization/protocol/http2-to-origin/	https://pedro-2025-10-27-docs-fix-build-warnings.preview.developers.cloudflare.com/speed/optimization/protocol/http2-to-origin/
https://developers.cloudflare.com/cache/advanced-configuration/serve-tailored-content/	https://pedro-2025-10-27-docs-fix-build-warnings.preview.developers.cloudflare.com/cache/advanced-configuration/serve-tailored-content/

[pedrosousa]

Build logs no longer contain the warnings:
https://github.com/cloudflare/cloudflare-docs/actions/runs/18841968197/job/53756221306#step:11:1