fix: correct relative imports after component reorganization

Fixed import paths for 43 components moved into features/ directories.
Key fixes:
- api/, types/, hooks/, state/, utils/ imports need ../../../ from features/*/
- components/ imports need ../../ from features/*/
- Cross-feature imports use relative paths (e.g., ../tool/tools-bottom-sheet)
- app-shell.tsx updated to import from features/ subdirectories

Frontend typecheck now passes except for one pre-existing error:
xterm-addon-webgl missing type declarations.

Quality gates: ruff passed on backend, py_compile passed on all backend files.

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

@@ -1,5 +1,5 @@
-import { Icon } from "./icon";
-import type { IconName } from "../utils/icons";
+import { Icon } from "../../icon";
+import type { IconName } from "../../../utils/icons";
 
 interface MobileListItem {
   id: string;