[AR-1206] - Rich Text Data Type

[Canopix]

Jira Ticket: https://ariessolutions.atlassian.net/browse/AR-1206

✨ Feature: Add support for “Rich Text” data type in custom object schema

This PR introduces a new "Rich Text" data type that can be added to a container’s schema. This allows users to define rich text fields when configuring a schema and edit those fields using the Lexical Editor.

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✅ Changes included

• Added new "Rich Text" option to the available data types in the schema configuration.
• When editing a custom object that includes a Rich Text field, the Lexical editor is rendered dynamically.
• On save, the Rich Text content is serialized to JSON using Lexical’s native generateJSON() API and stored as part of the custom object payload.

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🖼️ Screenshots

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🧪 How to test

1. Go to schema builder and add a new field with type Rich Text.
2. Create a new custom object using that schema.
3. Type into the rich text editor (e.g. bold, bullet list).
4. Save the object and confirm JSON is saved in the backend.
5. Reopen the object and confirm content is restored correctly.