[Internal] Host Agnostic Unified Provider

[tanmay-db]

Changes

Makes the unified provider host agnostic by unifying GetWorkspaceClientForUnifiedProvider into a single flow that works identically for workspace, account, and unified host configurations.

Previously, the function branched on HostType() to select between two separate code paths with duplicated validation logic. Now, a single flow handles all host types — it tries the provider's workspace client first, validates when possible, and falls through to account API resolution when the provider doesn't know its own workspace ID.

Also simplified NamespaceValidateWorkspaceID to delegate to the same unified flow.

Tests

• Unit tests
• Integration tests

NO_CHANGELOG=true

[github-actions]

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Trigger:
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Inputs:

• PR number: 5547
• Commit SHA: 7d2b69e40f9ff36d71bd6f3f00e321a817136aec

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