Update partitionKey path definitions for cosmosDatabase containers.

[crickman]

Motivation and Context

Customer issue reported in #238 related to partition scheme in cosmosdb containers.

Description

Update partition-key path definition for ChatMessage, ChatPartitipant, and MemorySource.

Existing deployments will continue to work in their current mode.

CosmosDB containers must be removed and redeployed to realize the peformance update related to the partition scheme.

Contribution Checklist

• The code builds clean without any errors or warnings
• The PR follows the Contribution Guidelines and the pre-submission formatting script raises no violations
• All unit tests pass, and I have added new tests where possible
• I didn't break anyone 😄

[dluc]

is there any table that should be partitioned by user?

[crickman]

TryFindByIdAsync

is there any table that should be partitioned by user?

No sir...this model is "chat-centric"

[dluc]

Another perf detail that came up is the consistency level. The tables are setup for "strong consistency" which could be relaxed to reduce latency.

[crickman]

Tested locally using https://ms.portal.azure.com/#@microsoft.onmicrosoft.com/resource/subscriptions/5b742c40-bc2b-4a4f-902f-ee9f644d8844/resourceGroups/crickman/providers/Microsoft.DocumentDB/databaseAccounts/crickman/overview