♻️ WIP: Updates related to Valet version change

- Centralized logic related to fetching Valet version.
- Updating global dependencies now updates the version number of Valet
  in the driver section.
- The latest version of Valet is now determined by checking Packagist.
  (This only occurs when the app starts up.)

tests/unit/_ST/Integration/PackagistTest.swift

@@ -10,7 +10,7 @@ import Testing
 
 @Suite("Integration")
 struct PackagistTest {
-    @Test func packagistRetrieval() async {
+    @Test func canRetrieveLaravelValetVersion() async {
         let packageToCheck = "laravel/valet"
         let latestVersion = try? await Packagist.getLatestStableVersion(packageName: packageToCheck)