fix: P0/P1 fixes (auth+limit+schema) + project audit docs

src/queries.js

@@ -187,10 +187,15 @@ async function getAllCompanies() {
  * @param {number|null} newLimit — новый лимит или null для сброса
  */
 async function setLimit(companyId, newLimit) {
-  await pool.query(
+  const result = await pool.query(
     'UPDATE companies SET custom_limit = $1, updated_at = NOW() WHERE id = $2',
     [newLimit, companyId]
   );
+  if (result.rowCount === 0) {
+    const err = new Error('Company not found: ' + companyId);
+    err.status = 404;
+    throw err;
+  }
 }
 
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