Preserve feel expression for unresolvable values

[nikku]

Proposed Changes

As a proposal built on top of #73 this PR preserves FEEL expressions for Any values, through the variable#info field. As a result it is shown during editor completion.

As per standard merging semantics different values will appear newline separated, this is covered in d435dec.

Checklist

Ensure you provide everything we need to review your contribution:

• Contribution meets our definition of done
• Pull request establishes context
  • Link to related issue(s), i.e. Closes {LINK_TO_ISSUE} or Related to {LINK_TO_ISSUE}
  • Brief textual description of the changes
  • Screenshots or short videos showing UI/UX changes
  • Steps to try out, i.e. using the @bpmn-io/sr tool

[nikku]

@barinali ready for review. Consider if this is really what we need, today - as per standard merging behavior different expressions (can be long ones) will be merged (concatenated via \n) - it will be hard to impossible (?) to distinguish them.

[Copilot]

Pull request overview

This pull request enhances the variable resolution system to preserve FEEL expressions for unresolvable variables (those that resolve to Any type) by storing them in the variable#info field. This enables the editor to display the original expression during completion, improving the developer experience.

Changes:

• Preserve FEEL expressions in the info field when variables cannot be resolved due to missing references
• Add test coverage for merging multiple unresolvable expressions with newline separation
• Update existing test expectations to reflect the new behavior where info contains the preserved expression

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 1 comment.

File	Description
lib/zeebe/util/feelUtility.js	Adds logic to preserve FEEL expression in info field when variable becomes Any due to unresolved references
test/spec/zeebe/Mappings.spec.js	Adds new test for merging any expressions and updates existing scope test to verify preserved expression
test/fixtures/zeebe/mappings/merging.any-expression.bpmn	New test fixture with two tasks outputting to same variable with different unresolvable expressions
CHANGELOG.md	Documents the new feature in the unreleased section

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[Copilot]

The CHANGELOG entry "preserve expression unresolvable values" could be clearer. Consider rewording to "preserve FEEL expressions for unresolvable values" or "preserve expressions in info field for Any-type variables" to better match the PR title and description.

Suggested change

	* `FEAT`: preserve expression unresolvable values ([#77](https://github.com/bpmn-io/variable-resolver/pull/77))
	* `FEAT`: preserve FEEL expressions for unresolvable values ([#77](https://github.com/bpmn-io/variable-resolver/pull/77))

[barinali]

@barinali ready for review. Consider if this is really what we need, today - as per standard merging behavior different expressions (can be long ones) will be merged (concatenated via \n) - it will be hard to impossible (?) to distinguish them.

As discussed today, I think there is still value in demonstrating merged expressions instead of not showing anything. This is, ideally, an intermediate state and I would like it to go in the direction of camunda/camunda-modeler#5697.