Add Azure Cosmos DB for MongoDB trigger, input, and output bindings

[xingfan-git]

Summary

This PR adds Node.js SDK support for the Azure Cosmos DB for MongoDB bindings, enabling
developers to trigger functions on MongoDB change stream events and read/write documents
from MongoDB collections using the Azure Functions programming model.

Changes

New Features

• app.cosmosDBMongo() — New function registration method for Cosmos DB for MongoDB
  triggered functions
• trigger.cosmosDBMongo() — New trigger factory for monitoring MongoDB change streams
  (supports Collection / Database / Cluster level)
• input.cosmosDBMongo() — New input binding factory for reading documents from a MongoDB
  collection, with optional queryString filter support
• output.cosmosDBMongo() — New output binding factory for upserting documents into a
  MongoDB collection
• Type definitions for CosmosDBMongoTriggerOptions, CosmosDBMongoTrigger,
  CosmosDBMongoFunctionOptions, CosmosDBMongoHandler, CosmosDBMongoInputOptions,
  CosmosDBMongoInput, CosmosDBMongoOutputOptions, and CosmosDBMongoOutput

Binding Type Strings

Binding	Type string
Trigger	cosmosDBMongoTrigger
Input	cosmosDBMongo
Output	cosmosDBMongo

Tests

Added test/cosmosDBMongo.test.ts with 12 test cases covering trigger, input, and output —
verifying type strings, all binding options, deterministic binding name generation, and
correct direction values via toCoreFunctionMetadata.

[swapnil-nagar]

@xingfan-git do you have a sample app, which would help me validate the changes?

[swapnil-nagar]

Sample app to validate this change