fix(combos): drop nullish entries in filterActiveConnections

`connection?.isActive !== false` evaluated to true for null/undefined
entries, so nullish elements survived the filter. Callers read properties
off the result — filterUsableConnections() reads `connection.testStatus`
— which would throw "TypeError: Cannot read properties of null".

Guard with an explicit truthiness check. Covered by a test that fails
against the previous predicate.

Reported-by: gemini-code-assist
Co-authored-by: diegosouzapw <diegosouza.pw@gmail.com>

src/shared/utils/connectionStatus.ts

@@ -16,13 +16,14 @@ export interface ConnectionActiveFlag {
 /**
  * Filters out connections that have been explicitly disabled
  * (`isActive === false`). Connections without an `isActive` field are
- * treated as active for backward compatibility.
+ * treated as active for backward compatibility. Nullish entries are
+ * dropped so callers can safely read properties off the result.
  */
 export function filterActiveConnections<T extends ConnectionActiveFlag>(
   connections: T[] | null | undefined
 ): T[] {
   if (!Array.isArray(connections)) return [];
-  return connections.filter((connection) => connection?.isActive !== false);
+  return connections.filter((connection) => !!connection && connection.isActive !== false);
 }
 
 /**

tests/unit/connection-status-filter-active-2526.test.ts

@@ -25,6 +25,18 @@ test("filterActiveConnections returns an empty list for invalid input", () => {
   assert.deepEqual(filterActiveConnections(null), []);
 });
 
+test("filterActiveConnections drops nullish entries instead of passing them through", () => {
+  // A nullish element must not survive: callers read properties off the
+  // result (e.g. `connection.testStatus`) and would throw a TypeError.
+  const active = { id: "active", isActive: true };
+
+  assert.deepEqual(filterActiveConnections([null, active, undefined]), [active]);
+  assert.doesNotThrow(() => filterUsableConnections([null, undefined]));
+  assert.deepEqual(filterUsableConnections([null, { id: "ok", testStatus: "active" }]), [
+    { id: "ok", testStatus: "active" },
+  ]);
+});
+
 test("filterUsableConnections applies the isActive gate before the testStatus gate", () => {
   // Regression for the exact bug: a disabled connection with a stale
   // "active" testStatus must NOT survive the combined filter that