[Waterfall] Save and restore Waterfall state

[mossy426-cdc]

Story Key: waterfall-view:save-restore-state

User Story

As a MicrobeTrace user, I want to save and restore the Waterfall view state, so that I can resume analysis without rebuilding the view manually.

Workflow / Use Case

Configure the Waterfall view, save or reload the session state, and confirm the restored app returns to the expected view configuration.

Expected Behavior

Waterfall preserves covered settings, selected data, and rendered state across session save and reload workflows.

Acceptance Criteria

• Given the linked QA tracker scenarios, when the user performs the covered Waterfall workflow, then the expected behavior remains true for each listed fixture and spec.
• Given the listed Cypress specs are run, when they pass, then this story has automated evidence for the grouped acceptance checks.
• Given linked QA evidence changes, when this story is regenerated, then tested fixtures, specs, and coverage notes stay aligned with the current QA trackers.

QA Tracker Evidence

• waterfall-view:W025
• waterfall-view:W026

Tested Against

Fixtures

• TestStyleNodelist_snp.csv
• TestStyleEdgelist_snp.csv

Cypress Specs

• cypress/e2e/journeys/flows/waterfall-session-roundtrip.cy.ts

Coverage Notes
Grouped from 2 QA tracker row(s): Session save and reload round-trip for Waterfall data; Saved Waterfall default view restores on session reload. Source areas: Session.

Source References

• User story row: docs/user-stories.csv#L101
• Branch: dev
• Commit: f4b481eb2242d2a89251300c3b94eaf09c842e04
• Generated by: mossy426-cdc
• Epic / Feature Group: Waterfall
• Story Type: Session Persistence
• Priority: P1
• Story Review Status: Draft
• Source Confidence: High
• Last reviewed: 2026-04-22

Story Notes

Generated as a grouped user story from QA tracker evidence. Review title and behavior language before enabling story_sync.

Definition of Done

• Acceptance criteria are satisfied.
• Linked QA tracker evidence remains current.
• Relevant Cypress coverage remains passing or any coverage gap is documented.
• Expected behavior remains distinguishable from bug or enhancement requests.

Manual Notes

Reviewer notes added below this line are preserved by future sync runs.