[Bug] sanitizerConfig works incorrectly

## Description

`BlockTool.sanitize` property returns an object with the same shape as Tool's `data` object. `sanitize` object container `SanitizerConfig` as leafs.

Examples:

```
{
text: {
br: true,
},
}
```

```
{
caption: {
text: { br: true }
}
}
```

Internal BlockTool class has `baseSanitizeConfig` and `sanitizeConfig` preoptries.

`baseSanitizerConfig` is merge of sanitize configs of inline tools and tunes used by Block tool

`sanitizeConfig` returns an object with the shape of original `tool.sanitize`, but each with merged `baseSanitizerConfig` to each property.

Example
Tool config: `{ text: { br: true } }`
Inline Tool config: `{ b: true }`
Tune config: `{ sup: true }`

`baseSanitizeConfig` would be `{ b: true, sup: true }`
`sanitizeConfig` would be `{ text: { br: true, b: true, sup: true } }`

## Problems
1. `baseSanitizeConfig` should be renamed so its name reflects it is a merge of Tunes and Inline Tools sanitize configs
2. Return type of `sanitizeConfig` should be changed to reflect shape of the `data` object
3. `sanitizeConfig` should be able to process nested fields of `data` object (also need to check the same in Saver module)