deleteQzoneMsg POSTs a form-urlencoded tid to taotao.qzone.qq.com's
emotion_cgi_delete_v6 (proxied through h5.qzone), on the bot's own space.
Success has no positive payload beyond code 0, so the contract is
throw-on-non-zero-code (foreign/unknown tid or auth failure); the server
only deletes feeds the hostUin owns. Rejects empty tid pre-flight.
- core: QzoneApi.delete; onebot: delete_qzone_msg action; regen catalog.
- tests: tid form-body/url/headers lock, empty-tid preflight, non-zero
code throw, and bridge self-space threading.