Update Saturn logger configuration

[lidel]

Extracting tasks fro bifrost-gateway from:
https://www.notion.so/pl-strflt/Saturn-Payments-Logging-8db8d7b691a9471aaf786947a6b8b0a6

Changes requested by Saturn:

• change default endpoint to https://logs.strn.network (HTTP POST), make it implicit (remove from CLI, but allow override via ENV STRN_LOGGER_URL)
• read logger token via ENV STRN_LOGGER_URL – confirmed this convention with George
• switch to latest caboose version
• create separate http client for log reporting, and add secret token to every log report (Authorization: Bearer <base64_jwt>) – see how here: Set JWT token on Saturn Logging client and config the correct logging endpoints #51 (comment)
• dont break local dev: send logs only when secret token is present, support local dev without it, or figure out how devs can get tokens if they are mandatory for caboose to operate correctly