Fix reported game issues and add collections

[asxrow66]

Summary

• Fixes narrow game cards by collapsing the primary Play/Install action into the overflow menu when there is not enough horizontal room.
• Adds local Mythic collections for games: store/preserve collection names on games, add/remove them in game settings, and filter/search by collections in the library.
• Preserves collections when storefront data is merged/refreshed.
• Delays the automatic Sparkle background update check until the next interval so the app can launch cleanly instead of firing the background updater immediately at startup.

Fixes #180
Fixes #188

Verification

• xcodebuild -scheme Mythic CODE_SIGNING_ALLOWED=NO SWIFTLINT=NO build ✅
• Opened the rebuilt Debug app locally; Mythic launches to the setup screen ✅
• swiftlint --quiet skipped locally: swiftlint is not installed