Some docs updates: (#163)

- Improve migration guide for qualified types like `FTS5`
  - Improve Tagged docs with custom representation example

Author: stephencelis

Sources/StructuredQueriesCore/Documentation.docc/Articles/DefiningYourSchema.md

@@ -270,7 +270,7 @@ To enable the trait, specify it in the Package.swift file that depends on Struct
 ```diff
  .package(
    url: "https://github.com/pointfreeco/swift-structured-queries",
-   from: "0.2.0",
+   from: "0.17.0",
 +  traits: ["StructuredQueriesTagged"]
  ),
 ```
@@ -305,6 +305,20 @@ RemindersList.leftJoin(Reminder.all) {
 }
 ```
 
+Tagged works with any query-representable value. For example, if you want a Tagged UUID to use the
+`UUID.BytesRepresentation` from StructuredQueriesSQLite:
+
+```swift
+@Table
+struct RemindersList: Identifiable {
+  typealias ID = Tagged<Self, UUID>
+
+  @Column(as: Tagged<Self, UUID.BytesRepresentation>.self)
+  let id: ID
+  // ...
+}
+```
+
 ### Primary keyed tables
 
 It is possible to let the `@Table` macro know which property of your data type is the primary

Sources/StructuredQueriesCore/Documentation.docc/Articles/MigrationGuides/MigratingTo0.18.md

@@ -16,3 +16,12 @@ helper module:
  import StructuredQueries
 +import StructuredQueriesSQLite
 ```
+
+If you are qualifying a SQLite-specific API, like the `FTS5` protocol, you must also update the
+qualification:
+
+```diff
+ @Table
+-struct ReminderText: StructuredQueries.FTS5 {
++struct ReminderText: StructuredQueries.FTS5 {
+```