Defers Electron window display until the renderer signals first
meaningful paint, avoiding initial blank screens or white flashes,
especially on startup and settings windows. Implements a handshake
using a renderer-to-main process message, color-matches background
to the current theme, and falls back to a timeout in development.
Also migrates font loading to npm packages, replaces Google Fonts
usage, and adds code-splitting for dialogs and quick switcher to
improve performance. Restricts console debug output to development.
LAPTOP-O016UC3M\Qi Chen
0ac351b41a