Editor UI changes

[ethanpalm]

Documentation changes

This PR updates the editor docs for recent UI changes.

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For Reviewers

When reviewing documentation PRs, please consider:

✅ Technical accuracy

• Code examples work as written
• Commands and configurations are correct
• Links resolve to the right destinations
• Prerequisites and requirements are accurate

✅ Clarity and completeness

• Instructions are clear and easy to follow
• Steps are in logical order
• Nothing important is missing
• Examples help illustrate the concepts

✅ User experience

• A new user could follow these docs successfully
• Common gotchas or edge cases are addressed
• Error messages or troubleshooting guidance is helpful

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Note

Low Risk
Documentation-only updates to reflect UI text/flows; no product logic or behavior changes.

Overview
Aligns the web editor docs with recent UI/wording changes across collaboration, publish, media, navigation, pages, and live preview.

Updates instructions to match the current UI (e.g., preview access via Publish and branch-based auto-updating previews; save/publish wording on feature branches; “file explorer” terminology and updated image alt text; consistent use of <Icon icon="plus" />/play button references), and simplifies formatting like inline URL examples.

^{Written by Cursor Bugbot for commit 0b6a891. This will update automatically on new commits. Configure here.}