Improve bilingual SDK documentation and build validation

[Jenson-LI]

Summary

• add 11 English/Chinese documentation pairs with language badges
• document verified code entry points, architecture boundaries, and build evidence
• remove plaintext historical test credentials from public READMEs
• fix compiler diagnostics across all five TLSR8258 example projects
• add repository validation and a checksum-pinned TC32 CI build

Validation

• python tools/validate_repository.py
• five clean TC32 GCC 4.5.1 builds, repeated twice
• 5/5 projects passed, 0 warnings, deterministic BIN SHA-256 values

说明

补充中英文 SDK 技术文档与自动验证，移除说明文档中的历史测试密钥，并以真实工具链验证五个示例工程全部零告警构建。尚未进行真实硬件、射频、配网或烧录验证。