Keeps a real, redacted error message instead of "Error: Error", surfaces Python tracebacks in Sentry as a vetted context, and adds an opt-in SNAPOTTER_SENTRY_DIAGNOSTIC verbose mode plus SNAPOTTER_SENTRY_DSN_OVERRIDE. The default fleet path ships nothing on the never-collect list; raw detail is reachable only via the opt-in flag. Also classifies Redis OOM/READONLY replies as operational and removes a ReDoS in stack-frame extraction.