Removes zero-consumer surface verified by repo-wide grep: the
reference-count render machinery, the never-called clearData chain,
unread snapshot fields (rangeMinutes, reason), dead refresh callbacks
on the connection hooks, the write-only wsRef sync, and the worker's
unreachable DEFAULT_CONFIG placeholder (now definite assignment under
the init-first client contract). No behavior change; the compressed
sampler path, samplerStats diagnostics, and lastTimestamp perf
contract stay. Net -120 lines across six files.
Tunglies
82d76113f2