fix(ci): graph schema smoke — checkpoint WAL before sql.js re-read

The smoke test asserts (a) the writer (better-sqlite3) succeeds and then
(b) re-reads the DB file via sql.js to verify the insert/migration landed.
Since #2431 put the writer in WAL mode (\`journal_mode = WAL\`), inserts
sit in the \`.db-wal\` sidecar until checkpointed; sql.js reads only the
main file and saw nothing. Symptoms: tests 2c, 3b, 5b all asserted false
even though tests 2a, 3a, 5a confirmed the writer succeeded.

Closing the writer connection (\`_resetBridgeDb\` calls
\`better-sqlite3.close()\`, which checkpoints WAL by default) before
each sql.js readback unblocks the verification. This is a smoke-script
bug surfaced by the Build V3 unblock — pre-3.14.2 the build broke before
this code ran, so the latent WAL incompatibility never tripped CI.

Local: 23/23 pass (was 18/23 with 4 WAL-related fails + 1 cascade).

Co-Authored-By: RuFlo <ruv@ruv.net>

scripts/smoke-graph-schema-migration.mjs

@@ -128,6 +128,13 @@ async function testEdgeInsert() {
     const count = await countGraphEdges(dbPath);
     assert(count === 1, `2b: graph_edges has 1 row (found ${count})`);
 
+    // Close the better-sqlite3 connection so its WAL is checkpointed back
+    // into the main DB file before we re-read via sql.js (#2431 added WAL
+    // mode for cross-connection safety; without this checkpoint, sql.js
+    // sees only the pre-insert main file and the inserted rows live in
+    // the .db-wal sidecar).
+    _resetBridgeDb();
+
     // Verify embedding_ref is inline-encoded
     const SQL = await loadSqlJs();
     const fileBuffer = fs.readFileSync(dbPath);
@@ -173,6 +180,9 @@ async function testLegacyIdPrefix() {
     });
     assert(ok, '3a: insertGraphEdge with mem:-prefixed IDs succeeds');
 
+    // Checkpoint WAL → main DB before re-reading via sql.js (#2431).
+    _resetBridgeDb();
+
     // Verify row exists with the prefixed IDs
     const SQL = await loadSqlJs();
     const fileBuffer = fs.readFileSync(dbPath);
@@ -262,6 +272,12 @@ async function testTableAutoCreate() {
     });
     assert(ok, '5a: insertGraphEdge succeeds on DB without graph_edges');
 
+    // Checkpoint WAL → main DB before re-reading via sql.js (#2431).
+    // Without this, sql.js sees only the pre-insert main file (just
+    // memory_entries) and the auto-created graph_edges table sits in
+    // the .db-wal sidecar, failing assertion 5b.
+    _resetBridgeDb();
+
     // Verify table was created
     const fileBuffer = fs.readFileSync(oldDbPath);
     const dbCheck = new SQL.Database(fileBuffer);