fix(examples): reject malformed notification responses

[fadi-george]

Description

One Line Summary

Reject malformed or ambiguous notification success bodies without retrying them.

Details

Motivation

Linear: SDK-5125, SDK-5118.

Only recognized subscription-indexing response shapes remain retryable. Null, primitive, array, malformed JSON, and ambiguous object bodies fail immediately. Adapted to CapacitorHttp and fetch from OneSignal/react-native-onesignal#1983.

Scope

All notification-send paths that exist in this repository: demo, demo_pods, demo_cap7, and demo-no-location. Published SDK APIs are unchanged.

Testing

• vp test run: 14 files and 224 tests pass; coverage thresholds pass.
• Added cases for malformed JSON, null, primitive, array, valid success, recognized transient failures, and ambiguous objects in all three retrying demos.
• Focused vp check passes for all changed service, test, Angular component, and no-location files.
• Production web builds pass for demo, demo_pods, demo_cap7, and demo-no-location.
• Full vp check has an unchanged baseline README.md formatting failure.

Affected code checklist

• REST API requests
• Public API changes

Checklist

• I have filled out all required sections
• PR does one thing
• No public API changes
• Automated tests pass
• Diff reviewed