AB#293018 - Safe in-app message casting

[kris-opti]

Description of Changes

The SDK force-cast remote message content to NSDictionary; when content was missing, null, a string, an array, or another unsupported type,

Changes:

• Parse required in-app message fields with Overlay-style safe casting (InAppMessageParser) instead of force-casts
• Skip malformed messages and only track delivery for successfully parsed payloads
• Add unit tests covering valid payloads and the crash-triggering content variants
• Bump version to 6.8.1 and update changelog

Breaking Changes

• None

Release Checklist

Prepare:

• Detail any breaking changes. Breaking changes require a new major version number
• Check pod lib lint passes
• Update any relevant sections of the repository wiki pages on a branch

Bump versions in:

• OptimoveCore.podspec
• OptimoveNotificationServiceExtension.podspec
• OptimoveSDK.podspec
• OptimoveCore/Sources/Classes/Constants/SDKVersion.swift
• README.md (no hardcoded version to update)
• CHANGELOG.md
• Update major version numbers in wiki (basic integration + push guides) (N/A — patch release)

Integration tests

T&T Only

• Init SDK with only T&T credentials
• Associate customer
• Associate email
• Track events

Mobile Only

• Init SDK with all credentials
• Track events
• Associate customer (verify both backends)
• Register for push
• Opt-in for In-App
• Send test push
• Send test In-App
• Receive / trigger deep link handler (In-App/Push)
• Receive / trigger the content extension, render image and action buttons for push
• Verify push opened handler

Deferred Deep Links

• With app installed, trigger deep link handler
• With app uninstalled, follow deep link, install test bundle, verify deep link read from Clipboard, trigger deep link handler

Combined

• Track event for T&T, verify push received
• Trigger scheduled campaign, verify push received
• Trigger scheduled campaign, verify In-App received

Release:

• Squash and merge to master
• Delete branch once merged
• Create tag from master matching chosen version
• Run pod trunk push to publish to CocoaPods

Post Release:

• Push wiki pages to master