[FEATURE] Add classifications(Tags) to assets

[abhinavmathur-atlan]

Is your feature request related to a problem? Please describe.
Currently, users cannot add, remove, or replace classification tags for assets directly through our MCP. This is a functionality we need to embed into the MCP for unlocking more use cases.

---

Describe the solution you'd like
We would like to extend the existing update_assets tool to support classification tag management. This should include the ability to:

• Add new tags to an asset (only if the tag already exists in the system)
• Remove existing tags from an asset
• Replace tag with a new tag (only existing tags are valid)

This ensures that asset metadata can be managed consistently within the same tool, avoiding duplication of functionality across multiple tools.

---

Technical Details

• Proposed API changes:

  • Update the update_assets tool to accept a new optional parameter for tags.
  • Support operations for add, remove, and replace within this parameter.
  • Add validation logic: before adding or replacing, ensure the tag exists in the system. If the tag does not exist, return a clear error.
  • Ensure backward compatibility by keeping existing update_assets functionality intact.

• Impact on existing functionality:

  • Users who need tag management gain new options without affecting those who do not.

• Required dependencies or new packages:

  • None, assuming classification tags are already modeled in the SDK.

---

Describe alternatives you've considered

• Creating a new dedicated tool for tag management. This was rejected to avoid fragmentation and keep asset updates consolidated in a single tool.

---

Additional context

• Use cases / scenarios:

  • A data steward wants to add a new "PII" classification tag to all assets containing sensitive information.
  • A project manager wants to remove outdated tags like "deprecated" after an asset is restored.
  • A compliance officer needs to replace all classification tags to align with updated governance policies, while ensuring only valid tags are applied.

• Implementation considerations:

  • Validate tags against the system registry before applying changes.
  • Consider bulk operations for large-scale tag updates.