ci: add build script and configuration for Netlify deployment

[YDX-2147483647]

Please leave this PR unmerged for a while to test netlify…
It works! Ready for review now.

Resolves #13

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[Copilot]

Pull Request Overview

This PR adds Netlify deployment configuration to the project by introducing a netlify.toml configuration file and a comprehensive netlify-build.sh build script. The build script automates the setup and build process for multiple documentation versions (en-US v0.14.0, v0.13.1, and ja-JP).

Key changes:

• Netlify configuration that executes the build script and publishes the _site directory
• Build script that installs dependencies (mise, sd, bun), fetches documentation assets from external sources, and builds multiple localized documentation versions
• Generation of an index page to navigate between different documentation versions

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 6 comments.

File	Description
netlify.toml	Configures Netlify to use the custom build script and specify the publish directory
netlify-build.sh	Implements automated deployment script that installs tools, fetches docs assets, generates index page, and builds multiple documentation versions

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[Copilot]

Pull Request Overview

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

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