Support custom HTTP methods in NetworkKMM

[bytemain]

Summary

• add VBTransportRequest/VBTransportResponse for custom HTTP methods
• support GET, POST, PUT, PATCH, DELETE, HEAD, and OPTIONS across Android, iOS, and OHOS paths
• pass the selected method through the OHOS libcurl wrapper and keep existing get/post APIs compatible

Verification

• GRADLE_USER_HOME=/tmp/codex-gradle-kuiklybase JAVA_HOME=$(/usr/libexec/java_home -v 22) ./gradlew :network:compileCommonMainKotlinMetadata --no-daemon
• GRADLE_USER_HOME=/tmp/codex-gradle-kuiklybase JAVA_HOME=$(/usr/libexec/java_home -v 22) ./gradlew :network:compileDebugKotlinAndroid --no-daemon
• GRADLE_USER_HOME=/tmp/codex-gradle-kuiklybase JAVA_HOME=$(/usr/libexec/java_home -v 22) ./gradlew :network:compileKotlinOhosArm64 --no-daemon
• GRADLE_USER_HOME=/tmp/codex-gradle-kuiklybase JAVA_HOME=$(/usr/libexec/java_home -v 22) ./gradlew :network:compileKotlinIosArm64 --no-daemon
• c++ -std=c++17 -fsyntax-only ... curl_wrapper.cpp

[tencent-adm]

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