Extract TraverseCore Swift package for iOS + macOS (#58)

[enricopiovesan]

Summary

• Add shared apps/traverse-starter/TraverseCore Swift package (HTTP sendCommand, SSE subscribe, AppStateViewModel, output parsing, macOS ServerDiscovery)
• Wire ios-swift and macos-swift to the local package; remove duplicated client/view-model sources
• Align Apple shells with the web-react SSE + command-dispatch pattern from Refactor web-react: replace useExecution polling with runtime SSE state subscription #43

Governing Spec

• 033-http-json-api — app SSE events
• 059-http-command-dispatch — command dispatch
• docs/design-language.md — three-zone UI shells

Project Item

• Closes Extract TraverseCore Swift package shared between ios-swift and macos-swift #58
• Project 2 item for Extract TraverseCore Swift package shared between ios-swift and macos-swift #58

Definition of Done

• TraverseCore package with Swift 6 / iOS 17+ / macOS 14+
• TraverseClient URLSession HTTP + SSE streaming
• AppStateViewModel @MainActor ObservableObject with runtime-owned state/output
• ServerDiscovery macOS-only .traverse/server.json reader
• Package unit tests for client, SSE payload mapping, view model
• ios-swift and macos-swift import local TraverseCore
• No UIKit/AppKit in TraverseCore

Validation

• cd apps/traverse-starter/TraverseCore && swift test (8 tests)
• xcodebuild iOS Simulator (iPhone 17) BUILD SUCCEEDED
• xcodebuild macOS BUILD SUCCEEDED

Architecture boundary

• UI shells render runtime fields only; transitions owned by Traverse SSE events
• Public HTTP/SSE surfaces only

Checklist

• Issue linked and Project 2 item updated
• Updated AGENTS.md blocked summary (Multi-capability showcase: traverse-starter.pipeline workflow (validate → process → summarize) #110 Ready after Traverse #620)
• No business logic added to UI layer
• CI gates pass locally where applicable

Made with Cursor