Add Flyout (Note-taking)

[gorkie]

Types of Changes

• New addition to list

Proposed Changes

Adds Flyout to the Note-taking section — a native macOS menu-bar app that slides a rich-text note panel out from the edge of the screen (code blocks, task lists, reminders, Markdown, iCloud sync). It sits in the same category as existing entries such as SideNotes and Quick Note.

• Added in alphabetical order (after Evernote) within the Note-taking section.
• Synced across all four language files: README.md, README-zh.md, README-ja.md, README-ko.md.
• Marked with the Native App icon (native AppKit/SwiftUI, not Electron). It is paid/proprietary, so no OSS/Freeware icon.

PR Checklist

• I have read the CONTRIBUTING guide
• I have explained why this PR is important
• I have added necessary documentation (if appropriate)