Poller Scaling Decisions (#553)

Added a proto that is optionally attached to task responses and contains data for the SDK about whether or not pollers should be scaled up or down.

Deprecate ScanWorkflowExecutions (#552)

Deprecate ScanWorkflowExecutions

Deprecate ScanWorkflowExecutions (#552)

Deprecate ScanWorkflowExecutions

add activity_paused flag to ByID heartbeat response (#517)

<!-- Describe what has changed in this PR -->
**What changed?**
Add "activity_paused" flag to RecordActivityTaskHeartbeatByIdResponse.

<!-- Tell your future self why have you made these changes -->
**Why?**
1. It is needed to let long-running activity know that activity was
paused on the server.
2. Because it is missing in RecordActivityTaskHeartbeatByIdResponse but
present in RecordActivityTaskHeartbeatResponse

<!-- Are there any breaking changes on binary or code level? -->
**Breaking changes**
No.

[Requires repository secret addition] Add Publish to Buf Github Action (

#508)

_**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?**
Adds a GitHub Actions workflow to automate the process of pushing
protocol buffers to the Buf registry on every push to the main branch.

We need to set the `BUF_TOKEN` secret before merging this PR.

<!-- Tell your future self why have you made these changes -->
**Why?**
We want to be able to depend on server protos from other repositories
(e.g. api-cloud) using the buf package manager.


<!-- 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**
NA

Warn PR authors about the merge policy (#500)

**What changed?**

Add a warning to the GitHub PR template reminding everyone that both
Server AND SDK teams must sign off on a PR before it's merged.

**Why?**

'Cause people have merged things a couple times now without SDK review.

**Breaking changes**

None

Release v1.42.0

Pause/Unpause/Reset definitions (#469)

* Pause/Unpause/Reset definitions

* work on comments

* regenerate opeapi

* working on comments

* add request_id to acitvity mutators

* fix comments

* more renaming

* more comments

* regenerate opeapi after merge

Remove buf breaking ignore (#468)

Add ShutdownWorker internal API (#443)

* Add ShutdownWorker internal API. 

This API will allow workers to signal shutdown/restart, which Matching can use to unload the shutdown worker's sticky task queue. This will effectively remove the latency incurred from tasks being pushed to a sticky worker after that worker has already been shutdown.