GCP v10.0: Prepare the blog post

[pose]

Draft in pulumi/docs with @pulumi/docs so it merges the moment v10 hits the registry. Scaffold with make new-blog-post.

Precedents: gcp-v9-release added by pulumi/docs#16027, and gcp-v8-release added by pulumi/docs#12791.

Prerequisites

• Find and link the upstream announcement for terraform-provider-google v8.0.0, or record that none was published. As of 2026-08-21 none exists, because upstream v8.0.0 has not shipped. For v7, HashiCorp published a GA post the day after release; for v6 there were two, HashiCorp's and Google Cloud's.

Acceptance criteria

• Draft PR at content/blog/gcp-v10-release/index.md.
• @pulumi/docs reviewed for style and supplied images.
• Links the migration guide and installation page.
• Carries a Neo-assisted-upgrade section, as v9 did.
• Merges when v10 appears on the registry, not before.