router-control: sync installation hardening

[katovpn]

Summary

• sync the unified Nikki/Mihomo install and update flow from the latest working copy
• add OpenWrt apk-tools 3.x installation support and safer package diagnostics
• harden Wi-Fi/LAN/password rollback timers, subscription User-Agent, DNS listener checks, and post-operation refresh

Safety notes

• public-source audit reports zero findings
• no release artifact is built or published by this PR
• live 5 GHz Wi-Fi and AdBlock DNS-path verification remain required before the next EXE

Files changed

• Router Control backend and web UI
• public profile manifest and README
• unit/integration tests

Verification performed

• 85 Python tests passed
• JavaScript syntax check passed
• Python compilation passed
• public-source audit passed for 33 files
• git diff check passed

Approval required

• review and live hardware verification are required before merge/release