fix: Use Ubuntu 22.04 Swift downloads with proper fallback chain

- Switch to Ubuntu 22.04 Swift downloads (compatible with Ubuntu 24.04)
- Add comprehensive Swift dependencies installation
- Implement fallback chain: 6.0.1 -> 6.0.2 -> 5.10.1
- Use correct download URLs: ubuntu2204 instead of ubuntu2004
- Add proper dependency packages for Swift runtime

Download URLs verified:
- Primary: Swift 6.0.1 for Ubuntu 22.04
- Fallback 1: Swift 6.0.2 for Ubuntu 22.04
- Fallback 2: Swift 5.10.1 for Ubuntu 22.04

🤖 Generated with [Claude Code](https://claude.ai/code)

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

Author: fatbobman

.github/workflows/linux-compatibility.yml

@@ -24,29 +24,47 @@ jobs:
       continue-on-error: true
       id: swift-setup
 
-    - name: Install Swift using Swiftly (fallback)
+    - name: Manual Swift installation (fallback)
       if: steps.swift-setup.outcome == 'failure'
       run: |
-        echo "Swift setup failed, installing Swift using Swiftly..."
+        echo "Swift setup failed, attempting manual installation..."
         
-        # Install Swiftly with non-interactive setup
-        echo "1" | curl -L https://swiftlang.github.io/swiftly/swiftly-install.sh | bash
+        # Install required dependencies
+        sudo apt-get update
+        sudo apt-get install -y binutils git gnupg2 libc6-dev libcurl4-openssl-dev libedit2 libgcc-9-dev libpython3.8 libsqlite3-0 libstdc++-9-dev libxml2-dev libz3-dev pkg-config tzdata unzip zlib1g-dev
         
-        # Add Swiftly to PATH for current session
-        export PATH="$HOME/.local/bin:$PATH"
+        # Try Swift 6.0.1 for Ubuntu 22.04 (should work on 24.04)
+        SWIFT_URL="https://download.swift.org/swift-6.0.1-release/ubuntu2204/swift-6.0.1-RELEASE-ubuntu22.04.tar.gz"
+        echo "Downloading Swift from: $SWIFT_URL"
         
-        # Install Swift 6.0 using Swiftly with Ubuntu 22.04 platform
-        echo "Installing Swift 6.0 using Swiftly..."
-        $HOME/.local/bin/swiftly install 6.0 --platform ubuntu2204
+        if curl -fsSL -o swift.tar.gz "$SWIFT_URL"; then
+          echo "Successfully downloaded Swift 6.0.1 for Ubuntu 22.04"
+        else
+          echo "Failed to download Swift 6.0.1, trying 6.0.2..."
+          SWIFT_URL="https://download.swift.org/swift-6.0.2-release/ubuntu2204/swift-6.0.2-RELEASE-ubuntu22.04.tar.gz"
+          if curl -fsSL -o swift.tar.gz "$SWIFT_URL"; then
+            echo "Successfully downloaded Swift 6.0.2 for Ubuntu 22.04"
+          else
+            echo "Failed to download Swift 6.0.2, trying 5.10..."
+            SWIFT_URL="https://download.swift.org/swift-5.10.1-release/ubuntu2204/swift-5.10.1-RELEASE-ubuntu22.04.tar.gz"
+            curl -fsSL -o swift.tar.gz "$SWIFT_URL"
+            echo "Downloaded Swift 5.10.1 as fallback"
+          fi
+        fi
         
-        # Use Swift 6.0
-        $HOME/.local/bin/swiftly use 6.0
+        # Extract Swift
+        echo "Extracting Swift..."
+        tar xzf swift.tar.gz
         
-        # Add Swift to PATH permanently
-        echo "$HOME/.local/share/swiftly/toolchains/6.0/usr/bin" >> $GITHUB_PATH
+        # Find the extracted directory
+        SWIFT_DIR=$(find . -maxdepth 1 -name "swift-*-ubuntu22.04" -type d | head -1)
+        echo "Swift directory: $SWIFT_DIR"
+        
+        # Add to PATH
+        echo "$PWD/$SWIFT_DIR/usr/bin" >> $GITHUB_PATH
         
         # Verify installation
-        $HOME/.local/share/swiftly/toolchains/6.0/usr/bin/swift --version
+        "$PWD/$SWIFT_DIR/usr/bin/swift" --version
     
     - name: Verify Swift installation
       run: |