[041] Implement iOS wrapper with Push, Keychain, and background tasks

[konard]

Parent epic: #1

Phase: Platform Wrappers
Priority: 41

Scope

Create the iOS wrapper and document App Store compliance constraints for messaging, agent automation, and wallet behavior.

Implementation Steps

• Select the iOS UI/runtime stack.
• Integrate Keychain and push notification boundaries.
• Document App Store review concerns for AI automation and crypto features.

Acceptance Criteria

• iOS build produces a runnable debug artifact.
• Secrets use Keychain-backed storage.
• Compliance notes are reviewed before store submission.

Automation

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