[ci skip] ci: add workflow_dispatch trigger to docfx workflow

.github/workflows/docfx.yml

@@ -3,6 +3,7 @@ name: DocFX
 on:
   push:
     branches: [ main ]
+  workflow_dispatch:
 
 jobs:
   docfx:

docfx_project/docfx.json

@@ -6,6 +6,7 @@
           "src": "../",
           "files": [
             "X10D/**/**.csproj",
+            "X10D.Hosting/**/**.csproj",
             "X10D.Unity/**/**.csproj"
           ]
         }