Initial commit: Next Step health management app

A calm, reliable app to help manage appointments, medications, and notes
for chemo patients and their families.

Features:
- Today dashboard with next appointment and medications due
- Medication tracking with multiple schedule types (fixed times, interval, weekdays, PRN)
- One-tap dose logging with 5-minute undo window
- Questions for doctor tracking
- Family sharing with workspace model and invite links
- Offline-first with IndexedDB and sync
- Docker Compose deployment with Tailscale Funnel support

Tech stack:
- Next.js 14 (App Router) + TypeScript + Tailwind CSS
- PostgreSQL + Prisma
- Argon2 password hashing + session cookies
- Dexie.js for IndexedDB

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

src/lib/auth/password.ts

@@ -0,0 +1,21 @@
+import * as argon2 from 'argon2'
+
+export async function hashPassword(password: string): Promise<string> {
+  return argon2.hash(password, {
+    type: argon2.argon2id,
+    memoryCost: 65536,
+    timeCost: 3,
+    parallelism: 4,
+  })
+}
+
+export async function verifyPassword(
+  hash: string,
+  password: string
+): Promise<boolean> {
+  try {
+    return await argon2.verify(hash, password)
+  } catch {
+    return false
+  }
+}