Swift 6 compatibility and naming convention fixes

- Update to Swift 6.0 tools version
- Add Sendable conformance to property wrappers
- BREAKING: Rename property wrapper types to follow Swift conventions:
  - @Embedded.json → @Embedded.JSON
  - @Embedded.yaml → @Embedded.YAML
  - @Embedded.text → @Embedded.Text
- Fix static methods to work without property wrappers
- Add SwiftLint configuration
- Fix all linting issues

Author: sdfsdhgjkbmnmxc

README.md

@@ -22,7 +22,7 @@ Add to your `Package.swift`:
 
 ```swift
 dependencies: [
-    .package(url: "https://github.com/botforge-pro/swift-embed.git", from: "1.3.0")
+    .package(url: "https://github.com/botforge-pro/swift-embed.git", from: "1.4.0")
 ]
 ```