feat: command handlers

Add all 11 Telegraf command handler files (tasks 12–16): log, skip, status, history, streak, snooze, settings-cmd, progress, next, reschedule, chat, and setup (including multi-step onboarding flow).

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

src/bot/commands/streak.ts

@@ -0,0 +1,34 @@
+import type { Context } from 'telegraf';
+import type { Database } from 'better-sqlite3';
+
+function getStreaks(db: Database): { current: number; longest: number } {
+  const rows = db.prepare(
+    "SELECT date FROM schedule WHERE status = 'completed' ORDER BY date ASC"
+  ).all() as Array<{ date: string }>;
+
+  if (rows.length === 0) return { current: 0, longest: 0 };
+
+  let current = 1, longest = 1, streak = 1;
+
+  for (let i = 1; i < rows.length; i++) {
+    const prev = new Date(rows[i - 1]!.date + 'T12:00:00');
+    const curr = new Date(rows[i]!.date + 'T12:00:00');
+    const diff = Math.round((curr.getTime() - prev.getTime()) / 86400000);
+    if (diff <= 2) {
+      streak++;
+      if (streak > longest) longest = streak;
+    } else {
+      streak = 1;
+    }
+  }
+
+  current = streak;
+  return { current, longest };
+}
+
+export function handleStreak(db: Database) {
+  return async (ctx: Context) => {
+    const { current, longest } = getStreaks(db);
+    await ctx.reply(`🔥 Current streak: ${current} sessions\n🏆 Longest streak: ${longest} sessions`);
+  };
+}