global.sx: persist/gappend records a pointer in a reserved $global index whose
seq is the global commit position; read-global/project-global replay every
event in commit order; global-from for incremental consumers. Opt-in (plain
append untouched); $-prefixed streams now reserved + hidden from the public
catalog (streams-all reveals them). Gives feed its unified timeline.
Deterministic across restart. 191/191.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
New backend op :streams (from seq high-water marks, so compacted streams still
list), threaded through mem-backend + durable serve/io-backend. catalog.sx:
persist/streams, stream-count, stream-exists?, total-events. 143/143.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
