[Feature] Perform workspace-level permission assignment by user_name, group_name, or service_principal_name

[alexott]

Changes

Use a previously not available API to perform permission assignment by user name, group name or SP application ID. This solves a long-standing problem with the assignment of principals by workspace administrators who don't have access to account-level APIs.

We got ok from Identity team for using this endpoint

Resolves #3412

Tests

• make test run locally
• relevant change in docs/ folder
• covered with integration tests in internal/acceptance
• tested manually
• using Go SDK
• using TF Plugin Framework
• has entry in NEXT_CHANGELOG.md file

[Copilot]

Pull Request Overview

This PR adds support for performing workspace-level permission assignments using user_name, group_name, or service_principal_name instead of requiring the principal_id. This addresses a long-standing limitation where workspace administrators needed account-level API access to retrieve principal IDs.

• Added new API method to handle permission assignments by name/identifier
• Extended the resource schema to support multiple principal identification methods
• Added comprehensive test coverage for the new functionality

Reviewed Changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
docs/resources/permission_assignment.md	Updated documentation with examples for the new name-based assignment methods
common/client.go	Added PutWithResponse helper method to support API calls that need response data
access/resource_permission_assignment.go	Refactored permission assignment logic to support both ID-based and name-based assignments
access/resource_permission_assignment_test.go	Added comprehensive tests for new assignment methods and error handling
NEXT_CHANGELOG.md	Added changelog entry for the new feature

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[github-actions]

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Inputs:

• PR number: 5068
• Commit SHA: dbc835bdc612c9d6a911705024701cc210b6e410

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