Phase 19: Complete elimination of TS2322 type assignment errors + build fix

[zanesq]

Phase 19 - Type Assignment Errors (TS2322) + Build Fix - COMPLETE! 🎉

Phase 19 Summary

• Target: 9 TS2322 "Type X is not assignable to type Y" errors
• Result: COMPLETE ELIMINATION - 9 → 0 errors (100% success)
• Total errors reduced: 73 → 63 (10 errors eliminated)
• Build error fixed: Resolved "await" in non-async function error
• Linting status: ✅ ZERO warnings maintained

Phase 19 Fixes Applied:

1. FlappyGoose.tsx: Fixed canvas ref type compatibility with callback ref approach
2. ProviderGrid.tsx: Fixed ProviderSetupModal prop names (model → _model, endpoint → _endpoint)
3. ExtensionList.tsx: Added missing disableConfiguration prop to interface and function parameters
4. SessionSharingSection.tsx:
   • Fixed Input onChange prop with conditional spread syntax
   • Fixed baseUrl type safety by ensuring string type for envBaseUrlShare
5. main.ts:
   • Fixed goosedProcess type declaration with proper ChildProcess union type
   • Fixed Content-Security-Policy header from array to string format
   • Fixed accelerator prop from null to undefined
   • Fixed destructuring assignment by using individual assignments
   • Fixed async/await issue in before-quit event handler (build fix)
6. goosed.ts: Added explicit return type annotation Promise<[number, string, ChildProcess]>
7. types/message.ts: Fixed getToolConfirmationContent return type to include | undefined

Build Error Resolution:

• Issue: "await" can only be used inside an "async" function in main.ts:1624
• Fix: Added async keyword to app.on('before-quit', async (event) => {
• Result: Build now compiles successfully

Technical Patterns Established:

• Proper ref handling with callback refs for complex type scenarios
• Conditional prop spreading for optional event handlers
• Type-safe environment variable handling with runtime type checks
• Explicit return type annotations for complex async functions
• Union types for nullable references in process management

Overall Project Status:

• Total Progress: 337+ errors eliminated from original ~400+
• Current Status: 84% reduction (63 errors remaining)
• Perfect Phases: 4 (Phase 12: Unknown errors, Phase 17: Property access, Phase 18: Index signatures, Phase 19: Type assignments)
• Build Status: ✅ Compiles successfully

Phase 19 achieved perfect completion with zero linting violations and resolved build issues! 🚀