Migrate snippets from fuel-gauge

[danielbate]

We currently have quite a few tests that references documentation from fuel-gauge. These scenarios are at times improperly formed in order to be more verbose and illustrate techniques rather than validate the end to end functionality of the SDK. As that is the intended usage of fuel-gauge, we should instead move fuel-gauge/src/doc-examples.test.ts to appropriate places in apps/docs-snippets. The documentation references will also need to be altered as the links will have been broken.

[petertonysmith94]

@danielbate pls

[danielbate]

Sorry meant to assign you @petertonysmith94

[petertonysmith94]

Notes:

• vector-4
  Doesn't show a return value in the documentation // expect value would be beneficial.

[petertonysmith94]

Unassigned the issue, moved the wallet code snippets and left the PR in draft. Might be helpful as part of #1919.

May be worth consideration while the docs revamp is in progress #1924