fix(version): print out version regardless of port-forwarding; pass through contexts

[FalcoSuessgott]

This PR prints out the kagent version even if a port-forwarding to the kagent server fails. In case the port-forwarding does not succeed, the unavailable versions will be marked as <unknown>:

Fixes: #868
Related to: #879

> go run cli/cmd/kagent/main.go version
Error starting port-forward: failed to establish connection to kagent-controller. error connecting to server. Please run 'install' command first
{"backend_version":"unknown","build_date":"unknown","git_commit":"none","kagent_version":"dev"}

Note: We might can consider removing the error message as it breaks the json output ...

Furthermore:

• This PR uses cmd.Context() consistently throughout all kagent subcommands.
• It adds a help Makefile target for a neat list of available Makefile targets

> make
controller-gen                 Download controller-gen locally if necessary.
envtest                        Download setup-envtest locally if necessary.
fmt                            Run go fmt against code.
generate                       Generate code containing DeepCopy, DeepCopyInto, and DeepCopyObject method implementations.
golangci-lint                  Download golangci-lint locally if necessary.
help                           list makefile targets
lint-config                    Verify golangci-lint linter configuration
lint-fix                       Run golangci-lint linter and perform fixes
lint                           Run golangci-lint linter
manifests                      Generate ClusterRole and CustomResourceDefinition objects.
run                            Run a controller from your host.
setup-envtest                  Download the binaries required for ENVTEST in the local bin directory.
vet                            Run go vet against code.

[Copilot]

Pull Request Overview

This PR fixes the version command to print the kagent CLI version regardless of whether port-forwarding to the kagent server succeeds. The changes ensure version information is always displayed, with remote versions reported as "unknown" when unavailable.

• Modified version command to use defer for version printing, ensuring it always executes
• Updated all port-forwarding operations to use cmd.Context() instead of a global context variable
• Added a help target to the Makefile

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
go/cli/cmd/kagent/main.go	Fixed version command to always print version info and updated context usage throughout CLI commands
go/Makefile	Added default help target for listing makefile targets

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[marcinkubica]

cheers for this one @FalcoSuessgott

I'm getting on mac m4, not sure if expected

 kagent version
{"backend_version":"unknown","build_date":"2025-10-08","git_commit":"7a264e9","kagent_version":"0.6.19"}
panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x2 addr=0x8 pc=0x101b90ffc]

goroutine 1 [running]:
github.com/kagent-dev/kagent/go/cli/internal/cli/agent.(*PortForward).Stop(0x0)
	/home/runner/work/kagent/kagent/go/cli/internal/cli/agent/utils.go:70 +0x1c
main.main.func7(0x14000788f08, {0x101d11703?, 0x4?, 0x101d11707?})
	/home/runner/work/kagent/kagent/go/cli/cmd/kagent/main.go:128 +0xcc
github.com/spf13/cobra.(*Command).execute(0x14000788f08, {0x1036c7340, 0x0, 0x0})
	/home/runner/go/pkg/mod/github.com/spf13/[email protected]/command.go:1019 +0x7bc
github.com/spf13/cobra.(*Command).ExecuteC(0x14000788008)
	/home/runner/go/pkg/mod/github.com/spf13/[email protected]/command.go:1148 +0x350
github.com/spf13/cobra.(*Command).Execute(...)
	/home/runner/go/pkg/mod/github.com/spf13/[email protected]/command.go:1071
github.com/spf13/cobra.(*Command).ExecuteContext(...)
	/home/runner/go/pkg/mod/github.com/spf13/[email protected]/command.go:1064
main.main()
	/home/runner/work/kagent/kagent/go/cli/cmd/kagent/main.go:336 +0x11b4