fix(database): cannot overwrite view bug

[ChrisPdgn]

This is my attempt to fix the "Cannot overwrite ... model" race condition

Concurrent calls to createView with the same viewName caused intermittent failures:

[ERROR] /database.DatabaseProvider/createView INTERNAL: Cannot overwrite … model once compiled.

This is a check-then-act race. Two calls both see this.views[viewName] as unset, then both try to register the same Mongoose model and create the same MongoDB view. The second fails because:

• mongoose.model(name, schema) throws OverwriteModelError if the name is already registered.
• createCollection({ viewOn }) can fail with NamespaceExists if the view already exists in MongoDB.

Typical triggers:

• Concurrent CreateResourceAccessList calls that resolve to the same hashed viewName.
• Multiple database instances handling database:create:view bus events.
• recoverViewsFromDatabase running many createView calls in parallel.

Solution

Two complementary mechanisms in the Mongoose adapter:

1. Promise coalescing (same process)

A pendingViewCreations map tracks in-flight work per viewName. A second caller awaits the same promise instead of starting duplicate registration / createCollection.

2. Catch-and-recover (multi-instance and leftovers)

• MongooseSchema constructor: catch OverwriteModelError and use the existing mongoose.model(name).
• createCollection: ignore NamespaceExists / “already exists” style errors (aligned with how SQL adapters tolerate duplicate view creation).

Testing results

I have observed that this error is always thrown when 2 database instances are deployed and tested this fix in that case. The error wasn't thrown successfully.

What kind of change does this PR introduce?

• Bugfix
• Feature
• Code style update
• Refactor
• Build-related changes
• Other (please describe)

Does this PR introduce a breaking change?

• Yes
• No

The PR fulfills these requirements:

• It's submitted to the main branch
• When resolving a specific issue, it's referenced in the PR's description (e.g. fix #xxx, where "xxx" is the issue number)

If adding a new feature, the PR's description includes:

• A convincing reason for adding this feature

Other information: