Does Pulumi v4 reject loose semantic version ranges for provider plugins, causing upgrade failures?

When upgrading a Pulumi project from the v3.x CLI to v4.x, the goal is to confirm whether the CLI will accept provider plugin version specifications that use loose semantic version ranges (for example, aws: ^4.0.0) or if it now requires an exact version match.

In Pulumi v3, the plugin resolver allowed such ranges and would download the latest compatible version, whereas v4 introduced stricter compatibility checks that may reject a range if no published version exactly satisfies the constraint.

Uncertainty remains about the exact behavior: does v4 treat a caret range as a minimum version requirement, does it fail to download a plugin when the range maps to no available version, and can the behavior be overridden through project configuration or CLI flags?