docs: adr 0012 sqlite only

architecture.mmd

@@ -86,15 +86,12 @@ graph TB
         A_COMMON["adapter-common<br/><i>Shared row conversions,<br/>error mapping, date utils</i>"]
         subgraph Storage["Storage"]
             A_SQLITE["sqlite<br/><i>SQLite repos</i>"]
-            A_PG["postgres<br/><i>PostgreSQL repos</i>"]
             A_SQLITE_SEARCH["sqlite-search<br/><i>FTS5</i>"]
-            A_PG_SEARCH["postgres-search<br/><i>tsvector/GIN</i>"]
             A_OBJ["object-storage<br/><i>S3 / filesystem</i>"]
         end
         subgraph Messaging["Messaging"]
             A_NATS["nats<br/><i>JetStream / Core</i>"]
             A_SQLITE_QUEUE["sqlite-event-queue<br/><i>Polling, dead-letter</i>"]
-            A_PG_QUEUE["postgres-event-queue<br/><i>Polling, dead-letter</i>"]
             A_EVT_PUB["event-publisher<br/><i>In-memory (tests)</i>"]
             A_PAYLOAD["event-payload<br/><i>Serde (de)serialization</i>"]
         end
@@ -107,7 +104,6 @@ graph TB
         subgraph Federation["Federation (feature-gated)"]
             A_AP["activitypub<br/><i>k_ap library</i>"]
             A_SQLITE_FED["sqlite-federation"]
-            A_PG_FED["postgres-federation"]
         end
         subgraph Media["Media Processing"]
             A_IMG["image-converter<br/><i>AVIF/WebP</i>"]