FEA-2771 Add ActionV2 w/o null safety

[sorenthompson-wk]

Motivation

Adding APIs in major versions introduces risk, since consumers with opened ranges could accidentally consume new APIs. So instead of exposing Action2 in w_flux 3.0, we will backpatch Action2 to a w_flux 2.x minor, so that it won't be an API addition in w_flux 3.0. This option enables us to start work on the Action migration before the w_flux major release has finished rolling out

Changes

Add Action2 and appropriate test coverage without null safety work.

Release Notes

Review

See CONTRIBUTING.md for more details on review types (+1 / QA +1 / +10) and code review process.

Please review:

QA Checklist

• Tests were updated and provide good coverage of the changeset and other affected code
• Manual testing was performed if needed
  • Steps from PR author:
  • Anything falling under manual testing criteria outlined in CONTRIBUTING.md

Merge Checklist

While we perform many automated checks before auto-merging, some manual checks are needed:

• A Frontend Architecture member has reviewed these changes
• There are no unaddressed comments - this check can be automated if reviewers use the "Request Changes" feature
• For release PRs - Version metadata in Rosie comment is correct

[aviary2-wf]

Security Insights

No security relevant content was detected by automated scans.

Action Items

• Review PR for security impact; comment "security review required" if needed or unsure
• Verify aviary.yaml coverage of security relevant code

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Questions or Comments? Reach out on Slack: #support-infosec.

[evanweible-wf]

Just some nits, otherwise LGTM. I'm also still working on a spike with Action0 and Action1 (for arity 0 and arity 1 since we talked about that alternative - we can compare them and see what we think.

[todbachman-wf]

I've just got some nits around the tests.

[evanweible-wf]

😆 this method name now works on two different levels

[sorenthompson-wk]

QA +1

• I saw the deprecation message for Action in my IDE.
• I ran the example app of w_outline with this branch of w_flux and the example app performed as expected.

[sorenthompson-wk]

@Workiva/release-management-p ready to merge

[rmconsole-wf]

+1 from RM