feat: add client/server version check mechanism to gRPC calls (#260)

* Add version check mechanism to gRPC calls

* Use semver not semver/v3

* Give dev builds a special "infinite" version number (999.0.0-dev)

* Handle no metadata on grpc call correctly for version check

* Move versioncheck package to root pkg/ from pkg/api/ since it is shared by both pkg/api/ and pkg/client/

* Only show "no daemon version" warning once

* Append version headers to metadata, not overwrite...

* Unit tests on versioncheck logic

* Move SetHeader to the ServerStream in ServerStreamInterceptor

* Go modernizer nits: interface{} -> any

* Use more conventional gRPC header names for version/min-versions

* Add TODO notes on checkDaemonVersionInResponse and related code that can be removed eventually after transition to version checking client/daemons

* Use testify for testing assertions

* Add explanatory comments on MinCLIVersion and MinDaemonVersion

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Co-authored-by: Pasha Sviderski <me@psviderski.name>

AGENTS.md

@@ -197,6 +197,7 @@ uc context use <name>           # Switch context
     - Integration tests in `test/e2e/`
     - Test fixtures in `test/fixtures/`
 - Use table driven tests whenever possible
+- Use the `testify` library for assertions (e.g., `require.Equal`, `assert.Nil`)
 
 ### Dependencies