[The Framework] 'Create new project' dashboard entry

[suleimansh]

Part of #297 (Bootstrap mode).

The dashboard front-door: a "Create new project" button that opens one question, "What do you want to build?", and kicks off bootstrap mode.

Scope:

• Entry point in the Projects sidebar, next to Add project.
• One prompt field with the approximate-idea-or-concrete-plan label from [The Framework] Bootstrap mode #297.
• A path/name input for where the new project goes (native folder picker later if we go desktop, App instead of localhost? #411).
• Calls the create-empty-project path, then starts the run in bootstrap mode.

Depends on the create-empty-project daemon path + the bootstrap system prompt.