Add `mkEnableTargetWith` and use it for documenting dynamic `autoEnable` conditions

[MattSturgeon]

[!NOTE] This PR is comprised of intentionally separate commits, please don't squash :slightly_smiling_face:

This is a solution to the issues uncovered by #1212. This should fix #98 (not tested).

• Avoid evaluating dynamic conditions while rendering the docs.
• Define literal expressions describing dynamic conditions.
• Tested: all workarounds can be removed in #1212, when merged with this PR.

Previously, the literal markdown same as `stylix.autoEnable` was used. When an additional conditionText is supplied, it will now use the literal expression stylix.autoEnable && ${expr}.

If the expr contains any nix operators with a lower priority than &&, it will be auto-wrapped in parentheses, unless autoWrapExpr = false is used.

We could stick with the previous markdown approach, but I'm unsure what the best way to approach merging it with a autoEnableExpr or autoEnableText or autoEnableMD style arg would be. Suggestions and/or followup PRs welcome.

Things done

• [x] Tested locally
• [ ] Tested in testbed
• [x] Commit message follows commit convention
• [ ] Fits style guide
• [ ] Respects license of any existing code used

Notify relevant people

• @Flameopathic : related to mkTarget

[MattSturgeon]

Rebased due to #1255

[0xda157]

merge conflict

[MattSturgeon]

merge conflict

Rebased :+1:

[MattSturgeon]

Rebased for conflicts

[MattSturgeon]

Updated mkTarget to use mkEnableTargetWith and support arguments like autoEnableExpr.

[MattSturgeon]

I would adapt my previous merge commit message (not squash commit message) proposal to the following:

SGTM

Let's optimistically close #98 with this patchset. If this issue is in fact not resolved, we can simply re-open it.

SGTM. There are likely other cases of unintentionally dynamic docs values this PR hasn't caught, since it doesn't introduce any enforcement. But let's be optimistic for now!

[stylix-automation[bot]]

Successfully created backport PR for release-25.05:

• #1470