Adds guide page on writing and using type annotations

What does this MR do and why?

This MR addresses Add frontend development doc to describe tools ... (#421733 - closed), which is a follow-up after Adding a script to generate jsconfig.json with ... (!77788 - merged) and Adds @types/lodash node_module (!128525 - merged).

It creates a new file called types.md under fe_guide folder.

How to set up and validate locally

See deployed app below.

MR acceptance checklist

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