feat: add flatpak support, window resolution options

[Keshav-writes-code]

This pull request introduces Flatpak packaging support for the Cherit app, updates licensing information to GPL-2.0 across the project, and includes dependency updates for the site. The main changes are grouped below:

Flatpak Packaging and Linux Distribution:

• Added Flatpak packaging configuration for Cherit, including io.github.keshav-writes-code.cherit.yml, metadata XML, and a submodule for Flatpak builder tools, enabling distribution on Linux via Flatpak. [1] [2] [3] [4]
• Updated tauri.conf.json to include the Flatpak metainfo XML in the Linux .deb package and increased default window size for a better user experience. [1] [2]

Licensing and Compliance:

• Added the full GPL-2.0 license text in LICENSE.md and updated license fields to GPL-2.0 in package.json (app and site) and Cargo.toml for Rust sources, ensuring clarity and compliance across the codebase. [1] [2] [3] [4]

Dependency Updates (Site):

• Updated several dependencies in the site’s package.json, including Astro, Starlight, Svelte, Prettier, and Unocss packages, to their latest versions for improved stability and security.

Let me know if you want to walk through the Flatpak build steps or have questions about the licensing changes.

[Copilot]

Pull request overview

This pull request introduces Flatpak packaging support for the Cherit application and standardizes the project license to GPL-2.0. The changes include configuration files for building Flatpak packages on Linux, updated licensing information across all package manifests, increased default window dimensions for better UX, and dependency updates for the site workspace.

Changes:

• Added Flatpak packaging infrastructure with manifest, metainfo XML, and builder tools submodule
• Updated license to GPL-2.0 across all package.json and Cargo.toml files
• Increased default window size from 800x600 to 1200x900
• Updated site dependencies including Astro, Starlight, Svelte, and UnoCSS packages

Reviewed changes

Copilot reviewed 19 out of 22 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
apps/app/distribute/linux/flatpak/io.github.keshav-writes-code.cherit.yml	Flatpak build manifest defining runtime, SDK, and build commands
apps/app/distribute/linux/flatpak/metainfo.xml	AppStream metadata for Flatpak distribution with app information
apps/app/src-tauri/tauri.conf.json	Updated window dimensions and added metainfo.xml to Linux deb package
package.json, apps/app/package.json, apps/site/package.json	Added GPL-2.0 license field
apps/app/src-tauri/Cargo.toml	Updated license field to GPL-2.0
LICENSE.md	Added GPL-2.0 license text
LICENSE	Removed GPL-3.0 license text
.gitmodules	Added flatpak-builder-tools submodule
apps/app/yarn.lock	Generated lockfile for app dependencies
apps/site/package.json	Updated multiple dependencies to latest versions

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[Copilot]

Corrected spelling of 'WSYIWYG' to 'WYSIWYG'.

Suggested change

	<summary>A WSYIWYG Markdown Editor Inspired by Obsidian</summary>
	<summary>A WYSIWYG Markdown Editor Inspired by Obsidian</summary>