chore: release 0.1.18

[pallaoro]

Cuts the 0.1.18 release — everything merged after v0.1.17 (#25, #26).

Features

• Attach files when creating a task — pick or drag files, shown as removable chips (feat: attach files when creating a task #25)
• "Attach image" in the terminal + menu — stages a real bitmap on the clipboard (from a clipboard image, a Finder-copied file read off disk, or a picked file) and forwards Ctrl+V so the agent attaches the actual pixels (fix finder image paste #26)

Fixes

• Paste a Finder-copied image file by path instead of a bare Ctrl+V, so it attaches the real file rather than a generic file-icon placeholder (fix finder image paste #26)

Release tooling

• Bump desktop app to 0.1.18