Main module version information is not stamped in toolchain binaries,
and therefore we do not have a program version for toolchain programs.

Rather than add special handling for toolchain programs in many places,
to handle the missing version, instead enforce the convention that for
toolchain programs, program version == go version.

Specifically:
- Add internal/telemetry.{IsToolchainProgram,ProgramInfo}, to share the
  logic for interrogating program information.
- Update ProgramInfo to reuse the go version as program version for
  toolchain programs.
- Update config generation to reuse the go version list as program
  version list, for toolchain programs.
- Use the go/version package rather than copying it, now that it is
  available. This means that the config generator requires go1.22, which
  should be fine as it is only run by developers or RelUI.
- Update config generation and validation to use go/version package
  rather than semver package for working with toolchain program
  versions.
- Move chartconfig.Validate to configgen.ValidateChartConfig, since
  validation now requires the go/version package and requires go1.22
  (chartconfig is linked by more packages).

For golang/go#67244

Change-Id: I226b18d37e1ad973002b19afa8afdb8cf97b358c
Reviewed-on: https://go-review.googlesource.com/c/telemetry/+/585198
Auto-Submit: Robert Findley <rfindley@google.com>
Reviewed-by: Hyang-Ah Hana Kim <hyangah@gmail.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>

A subsequent CL will fix the parsing/validation to ensure that this
would have been caught. For now, let's unbreak the config.

Updates golang/go#67244

Change-Id: I0a867cd7f4547085e6d027f486a069ff8a4e2c4f
Reviewed-on: https://go-review.googlesource.com/c/telemetry/+/585376
Reviewed-by: Michael Matloob <matloob@golang.org>
Reviewed-by: Hyang-Ah Hana Kim <hyangah@gmail.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Auto-Submit: Robert Findley <rfindley@google.com>