fix(obsidian-sync): remove mem_limit; add enable_cors

mem_limit: 768m causes the kernel cgroup OOM killer to fire before
the Erlang VM writes its first log line on a swap-heavy host — manifests
as exit code 1 / empty docker logs / OOMKilled:false (kernel kill, not
Docker's own cgroup reporter). Removing the limit lets CouchDB start.

Also adds enable_cors = true to [httpd] — required in CouchDB 3.x for
the [cors] section to take effect (without it CORS headers are silently
dropped).

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

obsidian-sync/couchdb/local.ini

@@ -24,6 +24,8 @@ require_valid_user = true
 
 [httpd]
 WWW-Authenticate = Basic realm="couchdb"
+# Required in CouchDB 3.x — without this the [cors] section below is ignored.
+enable_cors = true
 
 # --- CORS -------------------------------------------------------------------
 # LiveSync runs inside browsers with DIFFERENT origins:

obsidian-sync/docker-compose.yml

@@ -23,9 +23,9 @@ services:
       # top of CouchDB's defaults without us editing the base file.
       - ./couchdb/local.ini:/opt/couchdb/etc/local.d/10-livesync.ini:ro
 
-    # Guardrail on a RAM-tight box. CouchDB idles ~150-300MB; cap keeps a runaway
+    # mem_limit intentionally omitted: on a swap-heavy box the cgroup OOM killer
-    # query from eating your headroom. Swap still absorbs brief spikes.
+    # fires before the Erlang VM writes its first log line (kernel kills it, so
-    mem_limit: 768m
+    # docker inspect shows OOMKilled:false — misleading). Re-add once swap < 50%.
 
     healthcheck:
       # _up is CouchDB's lightweight liveness endpoint (no auth needed).