Better separate type declarations

[mkslanc]

Issue #, if available:

Description of changes:
This update builds on the work from #5427 to refine the TypeScript declaration generation, now producing separate, module-specific declaration files.

Ace documentation demo

Benefits:

• More navigable type definitions
• Public interfaces split from main declarations
• Unused imports removed, simplifying code
• Clearer documentation and enhanced IDE support
• Aligned with ace-builds and ace-code structures
• Internal and private elements filtered out

Result:
These changes yield a cleaner, more maintainable public API surface.

Before:

After:

Discussion Point: Allowing Index Signatures for Classes
We could consider adding an index signature to the class to allow dynamic properties. This can be helpful when properties are not known at compile time but need to be added later.

class Editor {
    [key: string]: any;
    ...
}

While this provides flexibility, it comes at the cost of reduced type safety, as any property can be added without restrictions.
Still could be a good tradeoff for situations like #5696 (comment)

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Pull Request Checklist:

• No backwards incompatible changes were made to Ace's public interface which is defined through the main typings file (ace.d.ts) and its references:
  • https://github.com/ajaxorg/ace/blob/master/ace.d.ts
  • https://github.com/ajaxorg/ace/blob/master/ace-modes.d.ts
  • https://github.com/ajaxorg/ace/blob/master/ace-extensions.d.ts

[github-actions]

One of the public type files has been updated, plase make sure there are no backwards incompatible changes done in the PR.

[github-actions]

One of the public type files has been updated, plase make sure there are no backwards incompatible changes done in the PR.

[github-actions]

One of the public type files has been updated, plase make sure there are no backwards incompatible changes done in the PR.

[github-actions]

One of the public type files has been updated, plase make sure there are no backwards incompatible changes done in the PR.

[github-actions]

One of the public type files has been updated, plase make sure there are no backwards incompatible changes done in the PR.

[github-actions]

One of the public type files has been updated, plase make sure there are no backwards incompatible changes done in the PR.

[github-actions]

One of the public type files has been updated, plase make sure there are no backwards incompatible changes done in the PR.