Address PR feedback - use Spectre.Console, remove old migrations, skip appsettings.json

- Replace CommandLineParser with Spectre.Console for CLI and colorful output
- Remove Migration_8_To_9 and Migration_9_To_11 (current version is 11.0)
- Make CurrentVersion dynamic based on highest ToVersion from migrations
- Skip version-controlled appsettings.json file during migration
- Update tests to reflect changes (9 tests passing)
- Enhanced help and version output with Figlet text and tables

Co-authored-by: linkdotnet <26365461+linkdotnet@users.noreply.github.com>

Author: Copilot

Directory.Packages.props

@@ -58,5 +58,6 @@
   <ItemGroup Label="Tools">
     <PackageVersion Include="CommandLineParser" Version="2.9.1" />
     <PackageVersion Include="Microsoft.Playwright" Version="1.57.0" />
+    <PackageVersion Include="Spectre.Console" Version="0.49.1" />
   </ItemGroup>
 </Project>

tests/LinkDotNet.Blog.UpgradeAssistant.Tests/Migration8To9Tests.cs

@@ -11,14 +11,13 @@ public MigrationManagerTests()
     }
 
     [Fact]
-    public async Task Should_Migrate_From_8_To_12()
+    public async Task Should_Migrate_From_11_To_12()
     {
         // Arrange
-        var testFile = Path.Combine(_testDirectory, "appsettings.json");
+        var testFile = Path.Combine(_testDirectory, "appsettings.Development.json");
         var json = """
             {
-              "BlogName": "Test Blog",
-              "KofiToken": "test123"
+              "BlogName": "Test Blog"
             }
             """;
         await File.WriteAllTextAsync(testFile, json);
@@ -32,8 +31,6 @@ public async Task Should_Migrate_From_8_To_12()
         result.ShouldBeTrue();
         var content = await File.ReadAllTextAsync(testFile);
         content.ShouldContain("\"ConfigVersion\": \"12.0\"");
-        content.ShouldContain("\"SupportMe\"");
-        content.ShouldContain("\"UseMultiAuthorMode\": false");
         content.ShouldContain("\"ShowBuildInformation\": true");
 
         // Verify backup was created
@@ -45,14 +42,12 @@ public async Task Should_Migrate_From_8_To_12()
     public async Task Should_Not_Modify_Already_Migrated_File()
     {
         // Arrange
-        var testFile = Path.Combine(_testDirectory, "appsettings.json");
+        var testFile = Path.Combine(_testDirectory, "appsettings.Production.json");
         var json = """
             {
               "ConfigVersion": "12.0",
               "BlogName": "Test Blog",
-              "ShowBuildInformation": true,
-              "UseMultiAuthorMode": false,
-              "ShowSimilarPosts": false
+              "ShowBuildInformation": true
             }
             """;
         await File.WriteAllTextAsync(testFile, json);
@@ -69,26 +64,35 @@ public async Task Should_Not_Modify_Already_Migrated_File()
     }
 
     [Fact]
-    public async Task Should_Handle_Invalid_Json()
+    public async Task Should_Skip_Version_Controlled_Appsettings_Json()
     {
         // Arrange
-        var testFile = Path.Combine(_testDirectory, "invalid.json");
-        await File.WriteAllTextAsync(testFile, "{ invalid json }");
+        var testFile = Path.Combine(_testDirectory, "appsettings.json");
+        var json = """
+            {
+              "BlogName": "Test Blog"
+            }
+            """;
+        await File.WriteAllTextAsync(testFile, json);
         var manager = new MigrationManager();
         var backupDir = Path.Combine(_testDirectory, "backups");
 
         // Act
         var result = await manager.MigrateFileAsync(testFile, false, backupDir);
 
         // Assert
-        result.ShouldBeFalse();
+        result.ShouldBeTrue();
+        var content = await File.ReadAllTextAsync(testFile);
+        content.ShouldBe(json); // Should not change
+        Directory.Exists(backupDir).ShouldBeFalse(); // No backup created
     }
 
     [Fact]
-    public async Task Should_Handle_Missing_File()
+    public async Task Should_Handle_Invalid_Json()
     {
         // Arrange
-        var testFile = Path.Combine(_testDirectory, "nonexistent.json");
+        var testFile = Path.Combine(_testDirectory, "appsettings.Invalid.json");
+        await File.WriteAllTextAsync(testFile, "{ invalid json }");
         var manager = new MigrationManager();
         var backupDir = Path.Combine(_testDirectory, "backups");
 
@@ -100,40 +104,27 @@ public async Task Should_Handle_Missing_File()
     }
 
     [Fact]
-    public async Task DryRun_Should_Not_Modify_File()
+    public async Task Should_Handle_Missing_File()
     {
         // Arrange
-        var testFile = Path.Combine(_testDirectory, "appsettings.json");
-        var json = """
-            {
-              "BlogName": "Test Blog",
-              "KofiToken": "test123"
-            }
-            """;
-        await File.WriteAllTextAsync(testFile, json);
+        var testFile = Path.Combine(_testDirectory, "nonexistent.json");
         var manager = new MigrationManager();
         var backupDir = Path.Combine(_testDirectory, "backups");
 
         // Act
-        var result = await manager.MigrateFileAsync(testFile, true, backupDir);
+        var result = await manager.MigrateFileAsync(testFile, false, backupDir);
 
         // Assert
-        result.ShouldBeTrue();
-        var content = await File.ReadAllTextAsync(testFile);
-        content.ShouldBe(json); // Should not change in dry-run mode
-        
-        // Verify no backup was created in dry-run mode
-        Directory.Exists(backupDir).ShouldBeFalse();
+        result.ShouldBeFalse();
     }
 
     [Fact]
-    public async Task Should_Apply_Partial_Migrations()
+    public async Task DryRun_Should_Not_Modify_File()
     {
         // Arrange
-        var testFile = Path.Combine(_testDirectory, "appsettings.json");
+        var testFile = Path.Combine(_testDirectory, "appsettings.Development.json");
         var json = """
             {
-              "ConfigVersion": "9.0",
               "BlogName": "Test Blog"
             }
             """;
@@ -142,15 +133,15 @@ public async Task Should_Apply_Partial_Migrations()
         var backupDir = Path.Combine(_testDirectory, "backups");
 
         // Act
-        var result = await manager.MigrateFileAsync(testFile, false, backupDir);
+        var result = await manager.MigrateFileAsync(testFile, true, backupDir);
 
         // Assert
         result.ShouldBeTrue();
         var content = await File.ReadAllTextAsync(testFile);
-        content.ShouldContain("\"ConfigVersion\": \"12.0\"");
-        content.ShouldContain("\"UseMultiAuthorMode\": false");
-        content.ShouldContain("\"ShowBuildInformation\": true");
-        content.ShouldNotContain("\"SupportMe\""); // Should not apply 8.0->9.0 migration
+        content.ShouldBe(json); // Should not change in dry-run mode
+        
+        // Verify no backup was created in dry-run mode
+        Directory.Exists(backupDir).ShouldBeFalse();
     }
 
     public void Dispose()