fix(macos): Propagate environment objects to sheet presentations

[anthonybiasi]

Summary

Fixes crash on macOS when presenting sheets due to missing @EnvironmentObject propagation.

Problem

The macOS app (v1.4.4) crashes with EnvironmentObject.error() when presenting SwiftUI sheets. This is a known SwiftUI behavior difference where macOS requires explicit environment object passing while iOS sometimes propagates them automatically.

Solution

Added .environmentObject(viewModel) to 8 sheet and fullScreenCover presentations in ContentView.swift:

• AppInfoView sheet (line ~191)
• FingerprintView sheet (line ~202)
• ImagePickerView fullScreenCover - iOS main context (line ~230)
• MacImagePickerView sheet - macOS main context (line ~259)
• ImagePreviewView sheet (line ~268)
• ImagePickerView fullScreenCover - iOS sheet context (line ~833)
• MacImagePickerView sheet - macOS sheet context (line ~854)
• LocationChannelsSheet sheet (line ~1392)

Testing Performed

• ✅ Built successfully on macOS
• ✅ All sheet presentations open without crash
• ✅ App Info sheet works
• ✅ Location channels sheet works
• ✅ People list sidebar works
• ✅ No console warnings about missing environment objects
• ✅ General app stability confirmed

Platforms Affected

• Fixed: macOS
• Tested On: macOS 26.1 (25B78) on Apple Silicon (M4)
• Not Affected: iOS (existing behavior maintained)

Impact

• Severity: HIGH (fixes app-breaking crashes)
• Risk: LOW (additive changes only, no logic modifications)
• Files Changed: 1 file, 8 line additions
• Backwards Compatibility: Fully maintained

Before/After

Before: Opening any sheet/modal crashed the app with EnvironmentObject.error()
After: All sheets open correctly, full functionality restored on macOS