Document how to properly configure React SDK Cadence imports

[jribbink]

Problem

Currently, we don't clearly callout how users should configure their React SDK (/FCL) project to import files and configuration from their Cadence project. The "Simple Frontend" demo intentionally simplifies this import to a string literally directly in the JS code, but this feels to be a footgun instead of an advantage.

This impacts AI tooling, where after searching our docs, it will always write Cadence as string literals instead of importing from a *.cdc file.

Suggested Solution

Personally, I feel that we should just demonstrate the correct import syntax in the Simple Frontend tutorial. We should always attempt to guide developers through our normative development process, and teaching developers to interact with the network in this way rather than perpetuating patterns that inevitably become problemmatic down the line.

The corollary would be, If we feel that the setup of the import syntax is too complicated to describe in our "Simple Frontend", it should be a signal that it's time to re-evaluate these patterns and investigate any improvements we can make to tooling (e.g. binding generation potentially offers a more streamlined development process).

Alternative Solution

Create a standalone page/tutorial. This is a foundational aspect of developer experience that just feels underdocumented right now.