[codex] Add docs architecture diagrams

[slideep]

Summary

• Add optimized WebP architecture diagrams for the top-level Luotsi system and live-view data path.
• Embed both diagrams on the Architecture concept page and the live-view sequence on the Live View workflow page.
• Add a scoped wide architecture-diagram figure style so dense system diagrams can render wider than normal prose without affecting existing tutorial screenshots.

Validation

• cmd.exe /c npm.cmd ci
• cmd.exe /c npm.cmd run build
• dotnet test Luotsi.Cli.Tests/Luotsi.Cli.Tests.csproj --filter "FullyQualifiedName~Website_Documentation_Links_Resolve|FullyQualifiedName~Website_Documentation_Sidebar_Slugs_Resolve"

Note: npm ci completed successfully and reported existing npm audit findings; this PR does not change package dependencies.

[Copilot]

Pull request overview

Adds new architecture diagrams to the documentation site and introduces a scoped figure style so dense system diagrams can render wider than standard prose without impacting existing tutorial screenshots.

Changes:

• Add a new figure.architecture-diagram style in the website CSS to render wide, centered, framed diagrams with captions.
• Embed two WebP diagrams on the Architecture concept page.
• Embed the live-view sequence diagram on the Live View workflow page.

Reviewed changes

Copilot reviewed 3 out of 5 changed files in this pull request and generated no comments.

File	Description
website/src/styles/site.css	Introduces scoped architecture-diagram figure styling (wider layout + framing) for dense diagrams.
website/src/content/docs/docs/core-workflows/live-view.mdx	Imports and embeds the live-view path sequence diagram under a new “Runtime path” section.
website/src/content/docs/docs/concepts/architecture.mdx	Imports and embeds top-level + live-view sequence architecture diagrams on the Architecture page.