docs: update the documentation page.

[thruflo]

Add a conceptual introduction to describe how to use the library. Reorganise the API reference. Add e2e examples for TanStack Query and Electric usage that illustrates typical collection type + mutationFn pattern.

https://github.com/TanStack/db/blob/thruflo/docs/docs/index.md

[changeset-bot]

⚠️ No Changeset found

Latest commit: 0450b81

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[pkg-pr-new]

examples/react/todo

npm i https://pkg.pr.new/@tanstack/db@73

npm i https://pkg.pr.new/@tanstack/db-collections@73

npm i https://pkg.pr.new/@tanstack/react-db@73

commit: 0450b81

[KyleAMathews]

Looking great!

We need to fit in somewhere that about how transaction lifecycles can be manually controlled.

E.g.

const addTodo = useOptimisticMutation({ mutationFn })

const addTodoTx = addTodo.createTransaction()

addTodoTx.mutate(() => {}

// user reviews change

// Another mutation
addTodoTx.mutate(() => {}

// Mutation is approved
addTodTx.commit()

[KyleAMathews]

Great stuff! A few minor suggestions but this is ready to go