Policy Management Interface implementation

[jalvaro-lks]

Description

As a contributor of the Industry Core Hub,
I want a Policy Management page accessible from the Policy icon in the header,
so that I can intuitively manage, create, edit, delete, search, filter, and group data access and usage policies across the dataspace.

Acceptance Criteria

• A new Policy Management page is available from the Policy icon in the header.
• The page provides a clean, intuitive, SharePoint-like UI optimized for managing a large number of policies.
• Policies can be created using existing policy JSON definitions, specifying:
  • Access or Usage policy type
  • Applicable data type
  • Control plane to register the policy
  • Policy version (Saturn or Jupiter)
• Policies can be edited and deleted from the page.
• Policies can be grouped, filtered, and searched (e.g. by Catalog Parts, Serialized Parts, or other relevant criteria).
• Selecting and switching the policy version (Saturn / Jupiter) is a highly visible and primary action on the screen.
• Common policy components can be reused when defining policies during resource sharing workflows (e.g. Catalog Parts, Serialized Parts, submodels).
• The visual style follows the dark theme and design guidelines of the existing Submodel Creator screen.

Additional Information

This task focuses on providing a design proposal for the Policy Management page, aligned with existing application styles and future integration into resource-sharing workflows. The initial scope assumes policy JSONs are created externally.

Backend implementation will be done in this issue #14