fix(injectModel): fix pre-existing index rollback and required-field duplicate precheck

[Copilot]

Two edge-case bugs in createUniqueIndexes and getUniqueFieldFilter that could cause silent data loss and missed duplicate detection on live collections.

Changes

• Rollback safety (createUniqueIndexes): Snapshot existing index names before the loop; only push indexes into createdIndexes if they weren't already present. The rollback path now exclusively drops indexes created by the current operation, preventing accidental destruction of pre-existing indexes when a later field fails.

const existingIndexNames = new Set((await Model.collection.indexes()).map(i => i.name));
// ...
const createdName = await Model.collection.createIndex({ [normalizedKey]: 1 }, indexOptions);
if (!existingIndexNames.has(createdName)) createdIndexes.push(createdName);

• Required-field duplicate precheck (getUniqueFieldFilter): For required fields, return {} instead of { [fieldKey]: { $exists: true } }. MongoDB's unique index treats all missing-field documents as duplicate nulls, so the old filter could pass the precheck while createIndex still throws error 11000.

function getUniqueFieldFilter(fieldKey, isRequired) {
  if (isRequired) return {}; // include missing-field docs
  return { [fieldKey]: { $exists: true, $ne: null } };
}

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Project	Deployment	Actions	Updated (UTC)
ur-backend-web-dashboard	Ready	Preview, Comment	Apr 2, 2026 8:23pm

[Copilot]

Pull request overview

This PR fixes two edge cases in the dynamic model injection utilities to prevent unsafe index rollback and improve duplicate detection before creating MongoDB unique indexes.

Changes:

• Make unique-index rollback safe by tracking only indexes newly created during the current createUniqueIndexes run.
• Adjust required-field duplicate precheck to include documents missing the field (aligning with MongoDB unique-index behavior for missing values).

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[Copilot]

Model.collection.indexes() will throw a NamespaceNotFound (code 26 / "ns not found") error when the collection doesn’t exist yet. createUniqueIndexes is called immediately after compiling a model for newly-created collections (before any inserts), so this can cause schema/collection creation to fail before any indexes are created. Consider wrapping the indexes() call in a try/catch and treating NamespaceNotFound as an empty index list (or ensuring the collection exists via Model.createCollection() / Model.init() before calling indexes()).

Suggested change

	const existingIndexes = await Model.collection.indexes();
	let existingIndexes = [];
	try {
	existingIndexes = await Model.collection.indexes();
	} catch (err) {
	const isNamespaceNotFound =
	err &&
	(err.code === 26 ||
	err.codeName === "NamespaceNotFound" ||
	err.message === "ns not found" ||
	(typeof err.message === "string" &&
	err.message.toLowerCase().includes("ns not found")));
	if (!isNamespaceNotFound) {
	throw err;
	}
	}