feat: 扩展 Rust gateway 全功能模块，新增 billing/crypto/wallet crate 及完整数据层

- 新增 aether-billing、aether-crypto、aether-wallet 独立 crate
- aether-data 扩展 repository 层：announcements、auth_modules、billing、
  candidate_selection、gemini_file_mappings、global_models、management_tokens、
  oauth_providers、proxy_nodes、quota、users、wallet 等模块
- aether-gateway 新增 api/auth/billing/control/middleware/scheduler/usage/
  video_tasks/hooks/maintenance/model_fetch/provider_transport 等功能模块
- 重构 executor decision 和 gateway state 为模块目录结构
- 新增 gateway router、frontdoor 路由层及对应测试
- Python 侧 API 路由重构，新增 compat/support 模块
- 前端 Logo 组件更新及 Provider 管理页面调整

crates/aether-crypto/Cargo.toml

@@ -0,0 +1,17 @@
+[package]
+name = "aether-crypto"
+version = "0.1.0"
+edition.workspace = true
+license.workspace = true
+repository.workspace = true
+description = "Shared crypto compatibility helpers for Rust migration"
+
+[dependencies]
+aes.workspace = true
+base64.workspace = true
+cbc.workspace = true
+hmac.workspace = true
+pbkdf2.workspace = true
+sha2.workspace = true
+thiserror.workspace = true
+uuid.workspace = true