Fix DocFX glob patterns and use string literal for config section

- Use standard api/**/*.yml and articles/**/*.md glob patterns
- Use string literal "GotenbergSharpClient" instead of nameof() in
  docs examples for clearer copy-paste usage

Author: Jaben

docs/articles/getting-started.md

@@ -53,7 +53,7 @@ dotnet add package Gotenberg.Sharp.Api.Client
 public void ConfigureServices(IServiceCollection services)
 {
     services.AddOptions<GotenbergSharpClientOptions>()
-        .Bind(Configuration.GetSection(nameof(GotenbergSharpClient)));
+        .Bind(Configuration.GetSection("GotenbergSharpClient"));
     services.AddGotenbergSharpClient();
 }
 ```
@@ -95,7 +95,7 @@ services.AddGotenbergSharpClient();
 
 ```csharp
 services.AddOptions<GotenbergSharpClientOptions>()
-    .Bind(Configuration.GetSection(nameof(GotenbergSharpClient)))
+    .Bind(Configuration.GetSection("GotenbergSharpClient"))
     .PostConfigure(options =>
     {
         options.BasicAuthUsername = Environment.GetEnvironmentVariable("GOTENBERG_USER");

docs/docfx.json

@@ -16,11 +16,11 @@
   "build": {
     "content": [
       {
-        "files": ["api/**.yml", "api/index.md"]
+        "files": ["api/**/*.yml", "api/index.md"]
       },
       {
         "files": [
-          "articles/**.md",
+          "articles/**/*.md",
           "articles/**/toc.yml",
           "toc.yml",
           "*.md"