implement chat messaging with event proposals

- Add functional chat with server communication and test responses
- Add ProposedEventCard component for confirm/reject actions
- Move Constants (Day, Month) from client to shared package
- Add dateHelpers utility for weekday calculations
- Extend Themes.tsx with button and text colors
- Update CLAUDE.md with current implementation status
- Add *.tsbuildinfo to .gitignore

packages/shared/src/models/Constants.ts

@@ -0,0 +1,39 @@
+export const MONTHS = [
+  "January",
+  "February",
+  "March",
+  "April",
+  "May",
+  "June",
+  "July",
+  "August",
+  "September",
+  "October",
+  "November",
+  "December",
+] as const;
+
+export type Month = (typeof MONTHS)[number];
+
+export const DAYS = [
+  "Monday",
+  "Tuesday",
+  "Wednesday",
+  "Thursday",
+  "Friday",
+  "Saturday",
+  "Sunday",
+] as const;
+
+export type Day = (typeof DAYS)[number];
+
+// Mapping for Date.getDay() which returns 0=Sunday, 1=Monday, etc.
+export const DAY_INDEX: Record<Day, number> = {
+  Sunday: 0,
+  Monday: 1,
+  Tuesday: 2,
+  Wednesday: 3,
+  Thursday: 4,
+  Friday: 5,
+  Saturday: 6,
+};

packages/shared/src/models/index.ts

@@ -1,3 +1,4 @@
 export * from './User';
 export * from './CalendarEvent';
 export * from './ChatMessage';
+export * from './Constants';