VersionStatus for WorkerDeploymentVersions (#595)

_**READ BEFORE MERGING:** All PRs require approval by both Server AND
SDK teams before merging! This is why the number of required approvals
is "2" and not "1"--two reviewers from the same team is NOT sufficient.
If your PR is not approved by someone in BOTH teams, it may be summarily
reverted._

<!-- Describe what has changed in this PR -->
**What changed?**
- add VersionStatus inside `WorkerDeploymentVersionInfo` +
`WorkerDeploymentVersionSummary`

<!-- Tell your future self why have you made these changes -->
**Why?**
- right now, the UI code deduces the status of a version by checking
`CurrentSince`, `RampingSince` and other attributes. This can just be
simplified by adding this enum and the server doing the heavy lifting
instead.

<!-- Are there any breaking changes on binary or code level? -->
**Breaking changes**
- None

<!-- If this breaks the Server, please provide the Server PR to merge
right after this PR was merged. -->
**Server PR**
- [741011](temporalio/temporal#7804)

Author: Shivs11