refactor: migrate all icons from Untitled UI to FontAwesome Pro Duotone

Replace all @untitledui/icons imports across 55 files with equivalent
@fortawesome/pro-duotone-svg-icons icons, using FontAwesomeIcon wrappers
(FC<{ className?: string }>) for prop-based usage and inline replacements
for direct JSX usage. Drops unsupported Untitled UI-specific props
(strokeWidth, numeric size). TypeScript compiles clean with no errors.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/components/application/date-picker/date-picker.tsx

@@ -1,6 +1,10 @@
+import type { FC } from "react";
 import { getLocalTimeZone, today } from "@internationalized/date";
 import { useControlledState } from "@react-stately/utils";
-import { Calendar as CalendarIcon } from "@untitledui/icons";
+import { FontAwesomeIcon } from "@fortawesome/react-fontawesome";
+import { faCalendar } from "@fortawesome/pro-duotone-svg-icons";
+
+const CalendarIcon: FC<{ className?: string }> = ({ className }) => <FontAwesomeIcon icon={faCalendar} className={className} />;
 import { useDateFormatter } from "react-aria";
 import type { DatePickerProps as AriaDatePickerProps, DateValue } from "react-aria-components";
 import { DatePicker as AriaDatePicker, Dialog as AriaDialog, Group as AriaGroup, Popover as AriaPopover } from "react-aria-components";