tanstack start docs

[drew-harris]

Adds tanstack start "getting started" docs.

For manual setup, if starting with the default project in npx @tanstack/cli create, and following the steps, you will end up with a site like:

The "paste this whole file" is slightly tweaked from the create-instant-app template to exclude auth.

[github-actions]

View Vercel preview at instant-www-js-drewh-tanstack-start-docs-jsv.vercel.app.

[drew-harris]

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📝 Walkthrough

Walkthrough

The changes add a new getting started guide for TanStack Start to the documentation site. This includes a new navigation entry in the docs navigation configuration and a corresponding markdown documentation page. The guide covers both automatic setup using Create Instant App and manual setup paths, with examples demonstrating how to integrate InstantDB with a TanStack Start application, including database schema definition and a sample Todo application implementation with read and write operations.

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Actionable comments posted: 1

🤖 Fix all issues with AI agents

In `@client/www/pages/docs/start-tanstack.md`:
- Around line 22-26: Update the callout text in the docs page by correcting the
typo "follwing" to "following" inside the {% callout type="warning" %} block so
the sentence reads "While the following setup guide..." (edit the string in the
callout content).