chore(perf): initialisation and rendering performance optimisations

[neSpecc]

Performance optimizations: initialization speed increased, blocks.render() API method optimized. Big documents will be displayed faster.

• Blocks will be added via a single DocumentFragment instead of a separate insertion.
• Event listeners are wrapped with requestIdleCallback to bind them after rendering.
• Removed await from core.ts module validation and initialization since they are not async.
• Some optimizations added at the Paragraph tool: chore: performance optimization editor-js/paragraph#71
• Toolbar and Inline Toolbar creation moved to requestIdleCallback

Initialization time with 2700 Blocks:

Before: 2000—3000ms
After: 250—350ms

Initialization Loader has been removed.

It led unnecessary layout, and also people asked about disabling it. It could be easily implemented outside the Editor.

Resolves #2340
Resolves #1305

The blocks.insertMany() API method was added. It allows inserting several Blocks into the specified index.

Just because we now have the BlockManager.insertMany() method. Also, someone asked about it in a Telegram channel.

I'll add tests for it to this PR soon.

Selection style won't override your custom style for ::selection outside the editor.

::selection selector moved to the .codex-editor scope

Resolves #1931

"Editor saving" and "I'm ready" logs removed

Annoying and unuseful.

Plugin cypress-terminal-report

For more detailed reports in cypres terminal output:

If tool throws error during render, we will use Stub tool instead of skipping

To save tool's data and let user know that he has that block in a document

BlockManager clear() method improved

Previously, it just removes blocks from .blocks Proxy. Now it destroys blocks instances and emits "block-removed" events.