style: fix all ruff and eslint errors across codebase

Backend (ruff):
- Fix 106 errors: move imports to top of file (E402)
- Remove unused imports (F401)
- Add missing imports for undefined names (F821)
- Remove unused variables (F841)
- Fix test_models.py broken RefreshToken test
- Fix test_projects_api.py missing TestClient import

Frontend (eslint):
- Remove unused imports/variables across 10 files
- Fix explicit any types in client.ts and sessions.ts
- Clean up empty block statements in terminal.tsx

Quality gates: ruff (pass), eslint (pass), tsc --noEmit (pass),
pytest (98 passed, 4 pre-existing failures)

apps/web/src/components/mobile-edit-view.tsx

@@ -1,5 +1,4 @@
 import { useState } from "react";
-import { Icon } from "./icon";
 
 interface FormField {
   name: string;

apps/web/src/components/mobile-list-view.tsx

@@ -22,8 +22,6 @@ interface MobileListViewProps {
 export const MobileListView: React.FC<MobileListViewProps> = ({
   items,
   onItemClick,
-  onItemDelete,
-  onItemDuplicate,
   emptyMessage = "No items found",
   searchPlaceholder = "Search...",
   onSearch,