Improve Console administration and local development workflow

[yuanzui-cf]

Objective

Improve the Console error experience, administrator resource management, project quota lifecycle, and local HTTP development workflow for version 0.1.0.

Scope

• Present application errors as Toast notifications and move the registration code field to the bottom of the signup form.
• Add searchable, filterable, multi-select tables for users, projects, and teams with safe bulk actions.
• Make soft-deleted projects visible to platform administrators and reliably release project and host quota.
• Add an explicit development mode that supports local HTTP testing without changing production defaults.

Acceptance Criteria

• Console errors are delivered through Toast notifications rather than inserted error text.
• Signup places the optional registration code after the other text fields.
• Deleted projects appear in the administrator project inventory and project quota is released even when external host cleanup fails.
• Administrators can search, filter, select multiple rows, and execute supported bulk actions for users, projects, and teams.
• Development mode can be enabled from configuration, environment, or CLI and is clearly documented.
• Targeted tests and just quality pass.

Constraints

• Preserve authentication, administrator authorization, audit history, and production security defaults.
• Keep the existing Vite+ and shadcn/ui stack.
• Pull requests for this work target the develop branch.

[yuanzui-cf]

Related existing issue: #147 covers project deletion quota cleanup and lifecycle auditing. It already belongs to the Product Capability Delivery parent, so GitHub does not allow attaching it to a second parent; this parent tracks the shared delivery scope.