User Portal agent listing improvements

[joelhulen]

User Portal agent listing improvements

The issue or feature being addressed

Fixes issues related to the order in which the User Portal retrieves agents and conversations (sessions). Issues include:

• Improperly deriving the agent and setting it to the selected agent when refreshing the browser while looking at a specific conversation
• Allowing the user to enter a prompt before the list of agents is available when there is a large number of conversations
• Perceived delay in populating the agents list on page load

Details on the issue fix or feature implementation

• Moved agent loading method call from the NavBar component to the init method of the app store
• Ensured the agent loading method call is moved to the top of the init method before session-loading logic occurs
• Updated the NavBar component to construct the agent options when the app store's agents collection has changed, rather than when the component is created

Confirm the following

• I started this PR by branching from the head of the default branch
• I have targeted the PR to merge into the default branch
• This PR needs to be cherry-picked into at least one release branch
• I have included unit tests for the issue/feature
• I have included inline docs for my changes, where applicable
• I have successfully run a local build
• I have provided the required update scripts, where applicable
• I have updated relevant docs, where applicable

Note

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