* Set "recommended project settings" for Mac app

* Add default fallback for font typingAttribute

* Clean up linter errors

* Update extension iconset

* Fix spm errors and upgrade sparkle (#203)

* Switch WriteFreely package import from ssh to https

* Sign macOS project target for Development

This fixes a crash-on-launch bug when running Product > Run from Xcode (Product > Archive should work correctly). See https://github.com/sparkle-project/Sparkle/issues/2056 for more details.

Bug introduced by commit:
671b0540ac

* Update Sparkle to v2.0 from official repo

Previously, we forked the repo to the WriteFreely org because Sparkle didn't support tag-based SPM updates. We therefore had to pull from the `master` branch, so forking insulated us from unexpected changes.

As of 2.x Sparkle now allows for tag-based updating via SPM; we'll allow patch updates but stop short of 2.1 until we can vet changes.

* Add MacUpdatesViewModel ObservableObject

* Use MacUpdatesViewModel to handle Sparkle update logic

Add action extension for Safari

Move user defaults to App Group

Migrate persistent store to App Group

Adapt new navigation to Mac app

Fix three-column navigation and various iOS 15 glitches

Throw (and handle) Keychain error instead of crashing

Override app delegate methods for window deminiaturization

Update URL for WriteFreely Swift package

Don't trigger navigation to Drafts list when creating new post

Use collection.url rather than server + collection alias in share sheets