Data Migration concurrency overhaul

[ualch9]

A continuation of #622...

• New DataMigration view, with a Report view for looking at the results of the migration.

Migration View	Migration Report View	Show Report

• If debugMode is on, Migrate Data in settings will always appear.
  • Drag-and-drop a userdefault plist file on the Continue button in the DataMigrationView to perform a test migration.
• Add OBAKitCore.UnstructuredError for arbitrary string errors.
  • Some error cases don't necessarily warrant an entire error case. Surfacing some sort of error text to the UI is preferred over an unexplained nil or print() and allows us to do better customer support (i.e. from a user screenshot).

---

• Rewrote DataMigrator in Swift Concurrency.
• Replace the DataMigrationBulletin with DataMigrationView, and DataMigrationReportView. It is currently not hooked up to the onboarding sequence.

        // High level implementation details of migration procedure
        //    ┌───────────┐
        //    │   START   │
        //    └─────┬─────┘
        //          ▼
        // ┌─────────────────────────────┐         ╔════════════════════════════╗
        // │ extractor.hasDataToMigrate? │──<NO>──▶︎║ throw .noDataToMigrate     ║
        // └────────┬────────────────────┘         ╚════════════════════════════╝
        //          │ <YES>
        //          ▼
        // ┌───────────────────┐              ╭─────────────────────────────────╮
        // │ Migrate User ID   │┄┄┄┄┄┄┄┄┄┄┄┄┄▶︎│ delegate.migrate(userID:)       │
        // └────────┬──────────┘              ╰─────────────────────────────────╯
        //          ▼
        // ┌───────────────────┐              ╭─────────────────────────────────╮
        // │ Migrate Region ID │┄┄┄┄┄┄┄┄┄┄┄┄┄▶︎│ delegate.migrate(regionID:)     │
        // └────────┬──────────┘              ╰─────────────────────────────────╯
        //          ▼
        // ┌───────────────────────────────────────────┐
        // │ Decode classic-OBA object, then           │
        // | get new-OBA object via APIService:        │
        // │   ╭───────────────────╮  ╮                │
        // │   │ Recent Stops      │  │                │
        // │   ╰───────────────────╯  │                │
        // │   ╭───────────────────╮  │ await until    │
        // │   │ Loose Bookmarks   │  │ all finished   │
        // │   ╰───────────────────╯  │     │          │
        // │   ╭───────────────────╮  │     │          │
        // │   │ Grouped Bookmarks │  │     │          │
        // │   ╰───────────────────╯  ╯     │          │
        // │        ┌───────────────────────┘          │
        // └────────┼──────────────────────────────────┘
        //          │
        //          ▼
        // ┌───────────────────────────────┐
        // │                               │                ╔═══════════════════╗
        // │ Check for any critical errors │ ─<has error>─▶︎ ║ rethrow error     ║
        // │                               │                ╚═══════════════════╝
        // └────────┬──────────────────────┘
        //          │ <no error>
        //          ▼
        // ┌───────────────────────────┐      ╭───────────────────────────────────╮
        // │ Migrate Recent Stops      │┄┄┄┄┄▶︎│ delegate.migrate(recentStop:)     │
        // └────────┬──────────────────┘      ╰───────────────────────────────────╯
        //          ▼
        // ┌───────────────────────────┐      ╭───────────────────────────────────╮
        // │ Migrate Loose Bookmarks   │┄┄┄┄┄▶︎│ delegate.migrate(bookmark:group:) │
        // └────────┬──────────────────┘      ╰───────────────────────────────────╯
        //          ▼
        // ┌───────────────────────────┐      ╭───────────────────────────────────╮
        // │ Migrate Grouped Bookmarks │┄┄┄┄┄▶︎│ delegate.migrate(bookmark:group:) │
        // └────────┬──────────────────┘      ╰───────────────────────────────────╯
        //          ▼
        //    ╔═══════════════╗
        //    ║ return report ║
        //    ╚═══════════════╝

---

Screen.Recording.2023-01-06.at.1.14.41.PM.mov

[aaronbrethorst]

@ualch9 this looks awesome, great work! I'll give it a proper review tomorrow.

[aaronbrethorst]

looks great! I noticed a couple strings that look like they need to be wrapped in OBALoc but otherwise I think it's good to go.

[aaronbrethorst]

@ualch9 looks good! I think this can be merged if you're ready to do so.