Possibility to manually create a Toolchain programmatically

[Vampire]

It would be nice to have a way to construct a toolchain from an arbitrary path programmatically.
For example we have a task that constructs a custom Java distribution.
For some tasks I want this to be used and not the "normal" toolchain configured for the build as a whole.
Currently with Gradle 6.8.2 I have to feed an empty provider to the tool property to clear the value including convention and then use executable to set the executable.
It would be nice if instead the task could expose a provider with a manually constructed toolchain from its output path that can then be used to set the tool property.

[stale]

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[bademux]

The feature will be nice for cross platform tasks like Jlink.