feat(ludic.telemetry): an event queue batched to a PostHog-shaped endpoint

Events are encoded once into lines held in memory; a batch is the first
lines joined, with the player id put in where a mark stood, POSTed on
Http's own thread every flush_ms or at flush_at events; a failure keeps
its lines and doubles the wait up to backoff_max; the queue is on disk
every save_ms and read back at the next start; off (the enabled port)
drops the request in flight, empties the queue and deletes the file; and
a run that may not send (can_send) keeps nothing. The player id is the
machine's own id (MachineGuid, IOPlatformUUID, /etc/machine-id) hashed
with the game's salt, else random; it lives in the game's id file beside
whatever else the game keeps there.

Ports: TelemetryWorld (can_send, enabled, now_ms, stamp) and
TelemetryTransport (send, poll, drop; unbound: Http). Config is a record
(host, key, path, lib, queue_file, id_file, id_salt, and the timings).
Facts: TELEMETRY_SENT, _FAILED, _ID. Not a System: it runs from a
launcher's first frame, before any world exists.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

packages/ludic.telemetry/package.ludic

@@ -0,0 +1,5 @@
+# ludic.telemetry - events queued in memory, batched to a PostHog-shaped endpoint, backed off when
+# offline, kept on disk between starts, and forgotten when the player says no. See README.md.
+package "ludic.telemetry"
+version "0.1.0"
+kind source