docs: fix inconsistencies, remove low informative twoslash examples

[sheremet-va]

Description

This PR removes almost all twoslash examples from docs. I left only those that give at least some useful information:

• show error that reports is not available in the workspace project
• show the power of vi.mock with import
• show hover information on expect example (this is also low on information, but it's good to showcase it at least once)

This saves time and memory during build.

Please don't delete this checklist! Before submitting the PR, please make sure you do the following:

• It's really useful if your PR references an issue where it is discussed ahead of time. If the feature is substantial or introduces breaking changes without a discussion, PR might be closed.
• Ideally, include a test that fails without this PR but passes with it.
• Please, don't make changes to pnpm-lock.yaml unless you introduce a new test example.

Tests

• Run the tests with pnpm test:ci.

Documentation

• If you introduce new functionality, document it. You can run documentation with pnpm run docs command.

Changesets

• Changes in changelog are generated from PR name. Please, make sure that it explains your changes in an understandable manner. Please, prefix changeset messages with feat:, fix:, perf:, docs:, or chore:.

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