refactor: Remove unused swift-perception dependency, target macOS 15+ only (#1)

- Remove `import Perception` from FetchSubscription.swift (was unused)
- Add explicit `import ConcurrencyExtras` for LockIsolated
- Remove swift-perception package dependency from Package.swift
- Update platforms to macOS 15+ only (drop iOS/tvOS/watchOS)
- Update Package@swift-6.0.swift similarly

The Perception import was never actually used - the file only uses
LockIsolated (from ConcurrencyExtras) and SharedReader (from Sharing).

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Co-Authored-By: Claude <noreply@anthropic.com>

Author: 2 people

Package.swift

@@ -5,10 +5,7 @@ import PackageDescription
 let package = Package(
   name: "sqlite-data",
   platforms: [
-    .iOS(.v13),
-    .macOS(.v10_15),
-    .tvOS(.v13),
-    .watchOS(.v7),
+    .macOS(.v15),
   ],
   products: [
     .library(

Package@swift-6.0.swift

@@ -5,10 +5,7 @@ import PackageDescription
 let package = Package(
   name: "sqlite-data",
   platforms: [
-    .iOS(.v13),
-    .macOS(.v10_15),
-    .tvOS(.v13),
-    .watchOS(.v7),
+    .macOS(.v15),
   ],
   products: [
     .library(

Sources/SQLiteData/FetchSubscription.swift

@@ -1,4 +1,4 @@
-import Perception
+import ConcurrencyExtras
 import Sharing
 
 /// A subscription associated with `@FetchAll`, `@FetchOne`, and `@Fetch` observation.