Upgrade to electron-forge 7.3.0

[adidahiya]

Changes in this PR:

• Upgrade to Electron v29.1
• Upgrade to electron-forge v7.3.x, which includes a few implicit breaking changes to module resolution & loading
• Upgrade to latest Vite v5.x
• Add "type": "module" to raga-app package.json
• Update electron-forge vite configs to use the suggested templates (adapted)
• Modify preload script to avoid using any Node.js APIs
• Modify raga-lib to use my fork of fluent-ffmpeg where I've converted the library from CommonJS to ES modules. This makes it easier for Electron Forge to load this dependency in the main/server entry points.

CI infra changes in this PR:

• Migrate from standard Ubuntu Linux environment to macOS execution environment
• Update Deno install path accordingly for macOS

Not done in this PR:

• Migrate @types/fluent-ffmpeg to my fork now that the shape of the export has diverged slightly

References:

• https://github.com/electron/forge/tree/1aa94fc32754ffd07a3652db42952f1f22ddbd6c/packages/template/vite-typescript/tmpl
• Undocumented breaking change for Vite plugin in v7.3.0 electron/forge#3506
• feat(plugin-vite): upgrade to vite@5 electron/forge#3468
• https://discord.com/channels/745037351163527189/746375169240727755/1210382027673702513

[adidahiya]

Things are working in dev mode now, but this seems to have broken the ffmpeg path in the production dist build (#67, 7b187d6).

Not sure if it's worth continuing to debug further at this point, spent nearly a whole day on it.

[adidahiya]

fixed by #245