refactor: update capability handling in Hierarchies operations

[itsyaasir]

Description of change

Capability Handling Overhaul

The capability retrieval system has been completely restructured to support package upgrades and improve type safety.

Before

• A generic get_cap() method that searched for capabilities using runtime-constructed struct tags.

After

• Two dedicated methods with proper deserialization:
  • get_root_authority_cap() – Retrieves RootAuthorityCap for administrative operations.
  • get_accredit_cap() – Retrieves AccreditCap for delegation operations.

Breaking Changes

Removed Capability enum

• The Capability enum (RootAuthority, Accredit) has been replaced with concrete struct types.

New capability structs

• New capability structs with proper MoveType implementations:

    pub struct RootAuthorityCap {
        pub id: UID,
        pub federation_id: ObjectID,
        pub account_id: ObjectID,
    }

    pub struct AccreditCap {
        pub id: UID,
        pub federation_id: ObjectID,
    }

API signature changes

• Capability retrieval now requires federation_id:

    // Old
    get_cap(client, Capability::RootAuthority, sender)

    // New
    get_root_authority_cap(client, owner, federation_id)

move_names module relocated

• Moved from operations.rs to types/mod.rs for better organization.

Fixes

• Package upgrade compatibility:
  • Capabilities are now found using find_object_for_address(), which searches across all package versions in history.
  • This fixes issues where capabilities created with older package versions could not be discovered.

Links to any relevant issues

Type of change

• Bug fix (a non-breaking change which fixes an issue)
• Enhancement (a non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation Fix

How the change has been tested

Change checklist

• I have followed the contribution guidelines for this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• I have added tests that prove my fix is effective or that my feature works
• I have checked that new and existing unit tests pass locally with my changes
• I have updated the CHANGELOG.md, if my changes are significant enough