Privacy fixes
- Remove Network cache keys and prefixes from diagnostic logs; these can contain client/device identities.
- Keep raw controller exceptions and MAC addresses out of client DPI, WiFi details, session-history and switch device-stat failure diagnostics.
- These four read paths now raise a safe
RequestErrorwith operation context and the exception class. Original exception context is suppressed in rendered tracebacks, following the existing Core privacy boundary.
Successful read results, requests and cache behavior are unchanged. Verified with canary regression tests, independent review, full CI and live reads. Network/API releases for the backlog require this version.