hermes - 💡(How to fix) Fix [Feature]: Kanban assignee should be a dropdown select instead of free text input

Title: [Feature]: Kanban assignee should be a dropdown select instead of free text input

Problem or Use Case

The Kanban WebUI currently uses a free text input for assigning tasks to profiles. This creates several UX problems:

1. Case sensitivity errors - Users must type profile names exactly (lowercase), but the WebUI displays them in uppercase due to CSS styling. This causes profile validation failures and task crash loops (see #21320).

2. No discoverability - Users must already know their profile names. There's no way to see available profiles without switching to the CLI (hermes profile list).

3. Copy-paste workflow - To avoid typos, users currently need to copy profile names from another source and paste them in, which is cumbersome.

4. Silent failures - When a profile name doesn't match exactly, the dispatcher fails with no clear notification to the user.

Proposed Solution

Replace the free text assignee input with a <select> dropdown that:

• Populates from the available profile list (fetched from backend or config)
• Shows profile names exactly as they exist (lowercase)
• Optionally includes profile descriptions/model info as secondary text
• Prevents invalid assignments at the UI level

Alternatives Considered

• Autocomplete/typeahead input - still allows typos, more complex to implement
• Input validation with error message - reactive rather than preventive
• Auto-lowercase on submit - doesn't solve discoverability or typo problems

Additional Context

Current profiles require exact matching against [a-z0-9][a-z0-9_-]{0,63} pattern. A dropdown would eliminate an entire class of user errors and make the Kanban board more accessible to new users.

Contribution

Happy to test or provide feedback on a PR.