[FEATURE] Add model selector for Dispatch

Preflight Checklist

• [x] I have searched existing requests and this feature hasn't been requested yet
• [x] This is a single feature request (not multiple features)

Problem Statement

A previous issue was incorrectly closed because the bot thought it found duplicate issues; they were not duplicates.

I want to choose the model I'm using via Dispatch. Currently it defaults to Opus 4.7 even when a lesser model will do fine.

Proposed Solution

Add a model selector on Claude Dispatch.

Alternative Solutions

None

Priority

Medium - Would be very helpful

Feature Category

Other

Use Case Example

I want to use less expensive models when using Dispatch.

Additional Context

_No response_