chore(test): cover unread large constraint-backing index in pgTAP and _STATIC_CHECKS

docs/health-checks/README.md

@@ -48,6 +48,7 @@ A check only fires when its conditions are met, so an empty result for any check
 - **Tables Larger Than 50GB** - Identifies tables larger than 50GB (but less than 100GB)
 - **Query Duration Logging Disabled** - `log_min_duration_statement = -1` so slow queries never get logged
 - **Known Bug Affecting Your Version** - Notable non-CVE bugs from PostgreSQL release notes that match your running version (data integrity, replication, vacuum). Covers PG 15-18.
+- **Unread Large Constraint-Backing Index** - Large unique or exclusion indexes (>100MB, 0 scans) that are still enforced on every write but never used for reads. The check fires on any `indisunique` or `indisexclusion` index, regardless of whether it backs a constraint. To clear the row: drop the index directly if it is standalone, or drop the underlying unique, primary-key, or exclusion constraint (PostgreSQL does not allow `DROP INDEX` on a constraint-backed index).
 
 ## LOW Priority Issues
 

testing/pgTAP/04_medium_tests.sql

@@ -2,7 +2,7 @@ BEGIN;
 -- Cache results once; querying inline per-assertion multiplies execution cost by N.
 CREATE TEMP TABLE _pgfa_func_results AS SELECT * FROM pg_firstAid();
 CREATE TEMP TABLE _pgfa_view_results AS SELECT * FROM v_pgfirstaid;
-SELECT plan(18);
+SELECT plan(20);
 
 SELECT ok(
     (SELECT count(*) >= 0 FROM _pgfa_func_results WHERE check_name = 'Missing FK Index'),
@@ -85,5 +85,14 @@ SELECT ok(
     'View executes Query Duration Logging Disabled check'
 );
 
+SELECT ok(
+    (SELECT count(*) >= 0 FROM _pgfa_func_results WHERE check_name = 'Unread Large Constraint-Backing Index'),
+    'Function executes Unread Large Constraint-Backing Index check'
+);
+SELECT ok(
+    (SELECT count(*) >= 0 FROM _pgfa_view_results WHERE check_name = 'Unread Large Constraint-Backing Index'),
+    'View executes Unread Large Constraint-Backing Index check'
+);
+
 SELECT * FROM finish();
 ROLLBACK;

testing/seed_and_validate.py

@@ -692,6 +692,8 @@ def start_session_threads(
         "Role Never Logged In",
         "Empty Table",
         "Index With Very Low Usage",
+        "Unread Large Constraint-Backing Index",
+        "Autovacuum Disabled On Table",
     }
 )
 
@@ -738,6 +740,15 @@ def start_session_threads(
         "Replication Slots Near Max Wal Size",
         "Table Bloat (Detailed)",
         "Idle Connections Over 1 Hour",
+        "Timestamp Without Time Zone",
+        "Varchar With Length Limit",
+        "Serial Column Legacy",
+        "Rules On Tables",
+        "Query Duration Logging Disabled",
+        "listen_addresses Wildcard",
+        "Known CVE Affecting Your Version",
+        "Known Bug Affecting Your Version",
+        "Not In With Subquery",
     }
 )