Merge remote-tracking branch 'origin/doc/host-client-group-readmes' into feat/directory-picker

scripts/gen-doc-graphs.ts

@@ -244,6 +244,14 @@ const SERVICE_ROLES: ServiceRole[] = [
     consumers: ['tool-todo', 'session-title', 'host-apiproxy'],
     note: 'Domains register state-driven fold units; the eager drive keeps per-session watermark states and api-proxy serves baselines and pushes changed values.',
   },
+  {
+    key: 'sessionProjectionCache',
+    pkg: 'session-projection-cache',
+    title: 'Persisted projection cache',
+    mode: 'core',
+    consumers: ['host-apiproxy'],
+    note: 'Durably checkpoints projection unit states per session (throttled + turn/end/detach mandatory points) and serves the cold-read ladder: cache row + persistence tail replay, so listings never load full logs.',
+  },
   {
     key: 'tui',
     pkg: 'tui',