feat: filter top-level resource with embed filter

This is enabled by adding `!inner` to the embedded resource

/projects?select=*,clients!inner(*)&clients.id=eq.12

This behaviour can be enabled by default with the config option

db-embed-default-join='inner'

Which saves the need for specifying `!inner` on every request.
If this is enabled, the previous behavior can be restored
per request by specifying `!left`  on the embedded resource.

/projects?select=*,clients!left(*)&clients.id=eq.12`

Tested on M20/02M/M2M relationships, views, RPC.

test/io-tests/configs/expected/no-defaults.config

@@ -12,6 +12,7 @@ db-schemas = "multi,tenant,setup"
 db-config = "false"
 db-tx-end = "rollback-allow-override"
 db-uri = "tmp_db"
+db-embed-default-join = "inner"
 jwt-aud = "https://postgrest.org"
 jwt-role-claim-key = ".\"user\"[0].\"real-role\""
 jwt-secret = "c2VjdXJpdHl0aHJvdWdob2JzY3VyaXR5"