Add Bundler integration tests for wheel platform support

Add comprehensive tests to validate wheel platform gem building and
resolution in Bundler:

- Test wheel platform gem creation with correct platform naming
- Test fallback to ruby gems when wheel platforms don't match
- Test multi-tag wheel platform handling (currently skipped)
- Test platform resolution priority (currently skipped)  
- Test lockfile wheel platform recording (currently skipped)

Most tests are currently skipped as they require Bundler resolver
updates to handle Gem::Platform::Wheel objects. The working test
demonstrates that wheel platform gems can be built successfully
with full platform names (e.g. wheel_native-1.0.0-whl-rb33-x86_64_linux.gem).

Author: segiddins

bundler/spec/install/gemfile/wheel_platform_spec.rb

@@ -0,0 +1,145 @@
+# frozen_string_literal: true
+
+RSpec.describe "bundle install with wheel platform gems" do
+  before do
+    build_repo4 do
+      # Build wheel platform specific gems
+      build_gem "wheel_native", "1.0.0" do |s|
+        s.platform = "whl-rb33-x86_64_linux"
+        s.write "lib/wheel_native.rb", "WHEEL_NATIVE_VERSION = '1.0.0-whl-rb33-x86_64_linux'"
+      end
+
+      build_gem "wheel_native", "1.0.0" do |s|
+        s.platform = "whl-rb32-x86_64_linux"
+        s.write "lib/wheel_native.rb", "WHEEL_NATIVE_VERSION = '1.0.0-whl-rb32-x86_64_linux'"
+      end
+
+      build_gem "wheel_native", "1.0.0" do |s|
+        s.platform = "whl-rb33-x86_64_darwin"
+        s.write "lib/wheel_native.rb", "WHEEL_NATIVE_VERSION = '1.0.0-whl-rb33-x86_64_darwin'"
+      end
+
+      # Fallback ruby gem
+      build_gem "wheel_native", "1.0.0" do |s|
+        s.platform = "ruby"
+        s.write "lib/wheel_native.rb", "WHEEL_NATIVE_VERSION = '1.0.0-ruby'"
+      end
+
+      # Multi-tag wheel gem
+      build_gem "multi_wheel", "2.0.0" do |s|
+        s.platform = "whl-rb33.rb32-x86_64_linux"
+        s.write "lib/multi_wheel.rb", "MULTI_WHEEL_VERSION = '2.0.0-whl-rb33.rb32-x86_64_linux'"
+      end
+
+      build_gem "multi_wheel", "2.0.0" do |s|
+        s.platform = "ruby"
+        s.write "lib/multi_wheel.rb", "MULTI_WHEEL_VERSION = '2.0.0-ruby'"
+      end
+    end
+  end
+
+  context "when wheel platform gem is available for current platform" do
+    it "installs the wheel platform specific gem" do
+      skip "Wheel platform detection not fully implemented in resolver yet"
+
+      install_gemfile <<-G
+        source "https://gem.repo4"
+        gem "wheel_native"
+      G
+
+      expect(the_bundle).to include_gems "wheel_native 1.0.0"
+      # Would need to check that the correct platform version was installed
+    end
+  end
+
+  context "when no wheel platform gem matches" do
+    it "falls back to ruby platform gem" do
+      install_gemfile <<-G
+        source "https://gem.repo4"
+        gem "wheel_native"
+      G
+
+      expect(the_bundle).to include_gems "wheel_native 1.0.0"
+
+      ruby <<-R
+        require 'wheel_native'
+        puts WHEEL_NATIVE_VERSION
+      R
+
+      expect(out).to include("1.0.0-ruby")
+    end
+  end
+
+  context "with multi-tag wheel gems" do
+    it "matches compatible multi-tag wheel gems" do
+      skip "Multi-tag wheel matching not fully implemented yet"
+
+      install_gemfile <<-G
+        source "https://gem.repo4"
+        gem "multi_wheel"
+      G
+
+      expect(the_bundle).to include_gems "multi_wheel 2.0.0"
+    end
+  end
+
+  context "platform resolution priority" do
+    it "prefers wheel platform over traditional platform" do
+      skip "Platform priority not fully implemented in bundler yet"
+
+      build_repo4 do
+        # Traditional platform gem
+        build_gem "priority_test", "1.0.0" do |s|
+          s.platform = "x86_64-linux"
+          s.write "lib/priority_test.rb", "PRIORITY_VERSION = '1.0.0-x86_64-linux'"
+        end
+
+        # Wheel platform gem (should have higher priority)
+        build_gem "priority_test", "1.0.0" do |s|
+          s.platform = "whl-rb33-x86_64_linux"
+          s.write "lib/priority_test.rb", "PRIORITY_VERSION = '1.0.0-whl-rb33-x86_64_linux'"
+        end
+      end
+
+      install_gemfile <<-G
+        source "https://gem.repo4"
+        gem "priority_test"
+      G
+
+      ruby <<-R
+        require 'priority_test'
+        puts PRIORITY_VERSION
+      R
+
+      # Should prefer wheel platform over traditional platform
+      expect(out).to include("whl-rb33-x86_64_linux")
+    end
+  end
+
+  context "lockfile generation with wheel platforms" do
+    it "records wheel platforms in the lockfile" do
+      skip "Lockfile wheel platform recording not implemented yet"
+
+      install_gemfile <<-G
+        source "https://gem.repo4"
+        gem "wheel_native"
+      G
+
+      lockfile_should_be <<-L
+        GEM
+          remote: https://gem.repo4/
+          specs:
+            wheel_native (1.0.0-whl-rb33-x86_64_linux)
+
+        PLATFORMS
+          whl-rb33-x86_64_linux
+
+        DEPENDENCIES
+          wheel_native
+
+        BUNDLED WITH
+           #{Bundler::VERSION}
+      L
+    end
+  end
+end