feat(docs): comprehensive documentation overhaul and CI setup

**Documentation rewrites (all components):**
- GeneralUpdate.Core — unified API reference with strategies, pipeline, events
- GeneralUpdate.Differential — Clean/Dirty semantics, algorithm selection, compression
- GeneralUpdate.Bowl — lifecycle, crash detection, backup recovery, BowlContext API
- GeneralUpdate.Drivelution — cross-platform driver update pipeline, batch/parallel modes
- GeneralUpdate.Extension — plugin management, manifest, query/install/update lifecycle
- GeneralUpdate.Tools — six modules, download methods, downstream consumers

**Cookbooks & guides:**
- Beginner cookbook — rewritten for new Hub-based sample structure
- Advanced cookbook — production deployment, CI/CD, enterprise integration
- Android auto-update — Maui & Avalonia documentation
- Architecture, Configuration, FAQ, Packaging, Pipeline, Security guides

**Architecture cleanup:**
- Remove GeneralUpdate.ClientCore and GeneralUpdate.Common (merged into Core)
- Define Docusaurus IA, sidebar structure, and i18n layout
- Reference Semantic Versioning (semver.org) in version standards

**CI & build:**
- Add src/GeneralUpdate-Samples.slnx solution file
- Update CI workflow: .NET build + website build verification
- Fix all broken markdown links for Docusaurus compatibility
- Remove broken image references

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Author: JusterZhu

.github/workflows/dotnet.yml

@@ -1,4 +1,4 @@
-name: .NET
+name: Build & Verify
 
 on:
   push:
@@ -7,27 +7,49 @@ on:
     branches: [ "main" ]
 
 jobs:
-  build:
-
+  # ═══════════════════════════════════════════════════════════════
+  # .NET Solution Build
+  # ═══════════════════════════════════════════════════════════════
+  dotnet:
+    name: .NET Build
     runs-on: ubuntu-latest
 
     steps:
     - uses: actions/checkout@v4
 
-    - name: Setup .NET 8
-      uses: actions/setup-dotnet@v4
-      with:
-        dotnet-version: 8.0.x
-
     - name: Setup .NET 10
       uses: actions/setup-dotnet@v4
       with:
         dotnet-version: 10.0.x
 
-    - name: Build ServerSample
-      run: dotnet build ./src/Server/ServerSample.sln
+    - name: Restore dependencies
+      run: dotnet restore ./src/GeneralUpdate-Samples.slnx
+
+    - name: Build solution
+      run: dotnet build ./src/GeneralUpdate-Samples.slnx --no-restore -c Release
+
+  # ═══════════════════════════════════════════════════════════════
+  # Docusaurus Website Build
+  # ═══════════════════════════════════════════════════════════════
+  website:
+    name: Website Build
+    runs-on: ubuntu-latest
+    defaults:
+      run:
+        working-directory: ./website
+
+    steps:
+    - uses: actions/checkout@v4
+
+    - name: Setup Node.js
+      uses: actions/setup-node@v4
+      with:
+        node-version: '20'
+        cache: 'npm'
+        cache-dependency-path: website/package-lock.json
+
+    - name: Install dependencies
+      run: npm ci
 
-    # Hub build requires local DLLs (libs/) or matching NuGet packages.
-    # Enable when NuGet packages are published from latest GeneralUpdate source.
-    # - name: Build Hub (NuGet mode)
-    #   run: dotnet build ./src/Hub/Hub.csproj -p:UseNuGet=true
+    - name: Build website
+      run: npm run build