Support auto-submit on selection (skipSubmitButton)

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🚨 IMPORTANT

This issue is likely user-facing in the main PostHog app, see surveyVersionRequirements.ts. If you delete or close this issue, be sure to update the version requirements list here.

Summary

The iOS SDK does not support the skipSubmitButton feature for surveys. This feature allows single-choice, multiple-choice, and rating questions to automatically submit when a selection is made, without requiring the user to press a submit button.

Current State

• The skipSubmitButton field is not present in PostHogRatingSurveyQuestion or PostHogMultipleSurveyQuestion structs
• The SwiftUI survey renderer does not handle auto-submission on selection

Expected Behavior

When a question has skipSubmitButton: true:

• For single-choice questions: submit automatically when an option is selected
• For rating questions: submit automatically when a rating is selected
• The submit button should be hidden for these questions

Implementation Notes

1. Add skipSubmitButton: Bool? field to relevant question structs in PostHog/Models/Surveys/PostHogSurveyQuestion.swift
2. Update the survey UI to conditionally hide submit button and trigger submission on selection

Reference Implementation

See posthog-js browser: packages/browser/src/extensions/surveys/components/QuestionTypes.tsx

Tracking

This is tracked in the survey SDK feature parity issue: PostHog/posthog#45658

This issue was generated by Claude during a Surveys SDK audit.