[Feature] 安卓端客户端支持(agent-mobile / Tauri)

[Islatri]

Affected area

Android Client (agent-mobile / Tauri)

Problem statement (what should this solve)

基于Tauri提供安卓客户端支持

Linked PR

1. feat(android): 安卓移动端初适配 (agent-mobile / Tauri) #467

Proposed behavior

1. UI基本基于agent-gateway
2. 安卓移动端适配基于Tauri实现
3. 后续逐渐接入安卓系统能力（如通知、悬浮窗、小组件、快捷操作等等）
4. 后续安卓开发PR均关联此Issue

Estimated change scope

crates/agent-mobile

Alternatives considered

考虑过直接在agent-gui里面进行cargo tauri android init，但是考虑到移动端的行为模式基本与agent-gateway中的相同（并且会多出一些系统能力），故另开agent-mobile并基于agent-gateway的前端移植；

Pre-submit checklist

• I searched existing issues and pull requests and found no duplicates.
• This proposal is focused on a single feature or improvement.
• I understand a PR should come after this issue is confirmed by maintainers, otherwise it will be converted to draft.