feat: versioning

[pd93]

There have been many issues raised over the content of version.go - The file where we get the Task version used for the --version flag and .TASK_VERSION variable.

• go-task --version unknown #1889
• Version set via ldflags is ignored when building from source tarball #1709
• Help setting version in Arch Linux package #1207
• --version doesn't work #1947
• build: honor version set by ldflag #2105
• Flag --version says "Task version: unknown" (pacman) #2150

Currently, we use a mixture of debug.ReadBuildInfo and -ldflags to set the version variable. The issue with this is that build info is only available when built with a Git checkout and -ldflags requires the maintainer of the release mechanism to maintain the version string/checksum correctly. Thins leads to inconsistencies between various builds.

This PR overhauls the whole thing to make some permanent improvements:

• When we run the release script, a version.txt file will be generated containing the version number
• The version.txt file is then embedded into the binary at build time using //go:embed
• This can still be overridden by -ldflags so we aren't breaking any existing overrides
• debug.ReadBuildInfo is queried and the commit/dirty status appended to the version if the information is available and is a development build (not tagged)
• Removed the Task version: prefix so that the output is easier to parse
• Removed the checksum

Examples:

# Any tagged build or when built outside a Git checkout
3.42.1
# Untagged commit in a Git checkout
3.42.1-2110245
# Uncommitted changes on an untagged commit in a Git checkout
3.42.1-2110245-dirty

[Copilot]

Copilot reviewed 4 out of 5 changed files in this pull request and generated 2 comments.

Files not reviewed (1)

• internal/version/version.txt: Language not supported

[vmaerten]

Nice !
I've added Copilot as reviewer to see if he has something good to say