deploy slice B + F: deploy/ artifacts + image-build + container smoke CI + tag-push publish (#26)

Co-authored-by: Aaron D. Lee <himself@adlee.work>
Co-committed-by: Aaron D. Lee <himself@adlee.work>

deploy/s6-rc.d/engine/dependencies.d/valkey-database

@@ -0,0 +1,3 @@
+# empty — engine doesn't WAIT on valkey (it must boot even if valkey is down
+# per ADR-0005's fail-safe posture: EventSink counts-and-drops, never blocks).
+# The dependency just orders boot for consistent log sequencing.

deploy/s6-rc.d/engine/run

@@ -0,0 +1,7 @@
+#!/command/execlineb -P
+# s6-rc service: rutster — the FOB. Runs the rutster binary (axum + media
+# thread + trunk WS + /metrics). Reads its env from the container env
+# directly (s6-overlay v3 inherits container env via s6-overlay-envdir —
+# this slice relies on the container env for simplicity; the per-service
+# env files are a future hardening step).
+exec /usr/local/bin/rutster