docs: rearrange browser guide

[MatanBobi]

Description

Following the idea to create an init command for browser mode (#5793), I suggested updating the doc page in the meanwhile to help people onboard more easily.
I rearranged the doc page a bit and added install commands as I think the motivation and drawbacks are less important for someone who navigates to this page as they're probably looking for an actionable checklist.

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:.

[MatanBobi]

Thanks for merging this @sheremet-va.
Is the first comment there correct? I received an error due to the fact I didn't have webdriverio installed.

[sheremet-va]

Thanks for merging this @sheremet-va. Is the first comment there correct? I received an error due to the fact I didn't have webdriverio installed.

The default will be changed: #5826

[MatanBobi]

The default will be changed: #5826

Nice, thanks for the quick answer :)