Add structured workflow control flow and V2 List tools (M4A)

[Paul Lizer (paullizer)]

Summary

• Add opt-in definition version 3 with structured If/else, explicit branch joins, task Run when/Skip, and safe later-sibling or branch-exit routing. Version-1/version-2 workflows retain their existing execution behavior.
• Extend the existing durable runner with exact node/execution/attempt identity, persisted path decisions, paged execution/decision records, frozen authorized references, and finite execution/deadline limits. Reuse native Analyze and the existing publication service without duplicating its destination ledger.
• Add personal/group V2 List authoring, typed condition and decision-field controls, explicit publication bindings, and paged run/attempt/receipt inspection. Classic retains run/cancel and refuses lossy advanced editing.
• Keep this independently releasable M4A slice separate from For each/Collect (M4B), Repeat until/publication-readiness extensions (M4C), and visual Flow authoring (M5).

Target: paullizer-react-v2-ui, based on 5cb06a4061feadbe99b105a76889b255f52081df. Analyze stabilization #1495 and screening #1494 are already merged into that target; they are not re-cherry-picked or duplicated in this PR.

Linked issue

No associated issue; the owner explicitly chose to continue without one. Builds on the merged workflow/Analyze integrations in #1484, #1483, and #1495.

Release Notes & Latest Features

• New Feature
• Bug Fix
• UI Enhancement
• Breaking Change
• Internal only

Is this visible to end users?

• Yes
• No

Is this admin-facing (Admin Settings, governance, deployment, config)?

• Yes — documented workflow execution limits; no new global capability toggle or deployment changes.
• No

Should this become a Latest Feature card?

• Yes
• No — not added in this incremental slice.
• Already added

Screenshot needed for the card?

• Yes
• No
• Attached

Release notes: deliberately left unchanged at the owner's request. Existing Analyze stabilization release notes are preserved.

Version bump

• application/single_app/config.py VERSION third segment bumped: 0.261.115 → 0.261.116.
• deployers/version.txt not changed because no deployers/ files changed.

Testing / validation

On the latest merged React V2 baseline:

• 144 targeted Python cases passed covering structured definitions/joins/routing, exact attempts and source access, durable restart/gates/limits, real task dispatch, native Analyze → saved join → existing publication service, legacy handoffs, editor stores, and route policies.
• 40 local browser tests passed using the real bundled V2 SPA and closed API fixtures: List authoring, safe conversion, unknown-schema read-only behavior, group scoping, mobile/keyboard editing, paged exact-attempt inspection, stale recovery confirmation, publication controls, retained V2 workflows, and the source-backed Classic guard.
• npm --prefix .\application\v2_ui run typecheck and npm --prefix .\application\v2_ui run build passed. The existing Vite large-bundle warning remains; no remote runtime assets were introduced.
• Swagger route check passed; changed-tree XSS and broken-access-control guardrails passed; python -m compileall -q .\application\single_app and git diff --cached --check passed.
• Documentation inventory coverage 7/7 and site-quality checks 6/6 passed. Regenerated inventory has no semantic change for these existing workflow surfaces.
• Earlier integration checks also passed the retained workflow contract/durability selection (303 tests + 93 subtests) and saved Analyze/model/publication selection (240 tests + 372 subtests). These counts overlap other selections and are not an aggregate suite total.

All fixtures use fictional data and isolated external-service boundaries. No live workflow, model endpoint, deployment, permission change, or document publication was used for acceptance.

Documentation

• Release notes left unchanged by explicit owner decision.
• Feature documentation: docs/explanation/features/WORKFLOW_STRUCTURED_CONTROL_FLOW.md; related data-flow/durability documents and create/trigger workflow guides updated.
• Admin workflow limit documentation updated; implementation and regression details are documented with this feature rather than a separate fix document.

Security checklist

• New Flask routes include @swagger_route(security=get_auth_security()) and existing Blueprint/user/group policies.
• No raw settings are newly sent to non-admin frontends; existing sanitized boundaries are retained.
• Browser JavaScript is served from local SimpleChat static assets only; no CDN-hosted JS.
• No secrets, keys, connection strings, or local-only artifacts are included.

Boundaries and follow-up

M4A deliberately accepts only empty iteration paths. The next slice must extend real execution identity, cursor/replay behavior, collection and provenance paging before admitting For each. Existing publication states are not redefined as indexed-and-ready; richer completion policies and generic aggregate adapters remain M4C. Live acceptance requires a separately authorized matching deployment. No PR merge or deployment is requested by this change.