fix: improve Docker socket detection and modernize app entry point

[Keralin]

Summary

• Docker context support: Detect Docker socket from docker context inspect instead of hardcoded paths
• Alternative runtimes: Add fallback support for OrbStack, Colima, and Rancher Desktop sockets
• Apple Silicon: Include /opt/homebrew/bin in PATH for Homebrew on M1/M2 Macs
• Modernize entry point: Replace deprecated NSApplicationMain() with NSApplication.shared.run()

Issues Fixed

• Fixes Ace Link does not respect docker contexts #77 - Ace Link does not respect docker contexts
• Fixes Latest version of Docker not detected if manually installed #76 - Latest version of Docker not detected if manually installed
• Fixes Use rancher desktop i.s.o. docker desktop #72 - Use rancher desktop i.s.o. docker desktop
• Fixes Implement Orbstack compatibility with acelink (almost working) #69 - Implement Orbstack compatibility with acelink

Changes

Process.swift:

• New dockerSocket property that checks docker context first, then falls back to known socket paths
• New getDockerContextSocket() method using docker context inspect
• Added OrbStack (~/.orbstack/run/docker.sock) and Colima (~/.colima/default/docker.sock) paths
• Added /opt/homebrew/bin to PATH for Apple Silicon

main.swift:

• Replaced deprecated NSApplicationMain() with modern NSApplication.shared.run()

Menu classes:

• Updated AppDelegate access to use NSApplication.shared.delegate as? AppDelegate

Test Plan

• Build succeeds with Xcode
• App launches and shows menu bar icon
• Stream opens successfully with Docker Desktop
• Test with OrbStack
• Test with Colima
• Test with Rancher Desktop