[Internal] Add host_type to HostMetadata

[tanmay-db]

🥞 Stacked PR

Use this link to review incremental changes.

• hosttype-metadata [Files changed]
  • default-oidc-audience [Files changed]
    • hosttype-resolved [Files changed]

---

Changes

Add host_type support to the SDK's host metadata discovery flow:

• Add host_type field to the HostMetadata dataclass, parsed from the /.well-known/databricks-config discovery endpoint response.
• Add HostType.from_api_value() static method to normalize host type strings ("workspace", "account", "unified") from the API into HostType enum values
  with case-insensitive matching.
• In Config._resolve_host_metadata(), populate a new _resolved_host_type attribute from the metadata's host_type field (does not overwrite if already set).

Tests

• Parametrized tests for HostType.from_api_value() covering all valid values, case variants, unknown strings, empty, and None.
• Tests for HostMetadata.from_dict with and without host_type.
• Tests for _resolve_host_metadata populating _resolved_host_type: happy path (unified), no-overwrite, missing metadata, and unknown strings.

[github-actions]

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Trigger:
go/deco-tests-run/sdk-py

Inputs:

• PR number: 1370
• Commit SHA: 32e3131473be4c2833c4adf8f70c779232f9a8fb

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[hectorcast-db]

Do we need this?
Unlike Go/TF, Python doesn't use the HostType at all.

[tanmay-db]

The changes were created to have consistency with Go SDK, since we don't need it right now, closing the PR