fix: apply WHERE filter to postgres sink, remove LIMIT from both sinks

The 100K queryids came from the postgres sink path having no filter
at all — not from the WHERE filter being too weak. LIMIT 100 was the
wrong fix; the filter itself is sufficient when applied everywhere.

- postgres sink (pgss_queryid_queries): add the same WHERE filter
  (calls >= 5 or total_exec_time >= 1000) instead of LIMIT 100
- prometheus sink (pg_stat_statements): remove LIMIT 100, keep
  the WHERE filter only

https://claude.ai/code/session_01SzJxzZNQjDQphaHyaX3RU7

Author: claude

config/pgwatch-postgres/metrics.yml

@@ -11,8 +11,8 @@ metrics:
         where
           queryid is not null
           and dbid = (select oid from pg_database where datname = current_database())
+          and (calls >= 5 or total_exec_time >= 1000)
         order by total_exec_time desc
-        limit 100
     gauges:
       - '*' 
 

config/pgwatch-prometheus/metrics.yml

@@ -1037,7 +1037,6 @@ metrics:
           from aggregated_statements
           where calls >= 5 or exec_time_total >= 1000
           order by exec_time_total desc
-          limit 100
       17: |
         with aggregated_statements as ( /* pgwatch_generated */
           select
@@ -1086,7 +1085,6 @@ metrics:
           from aggregated_statements
           where calls >= 5 or exec_time_total >= 1000
           order by exec_time_total desc
-          limit 100
     gauges:
       - calls
       - plans_total