feat: port remaining cohort scripts and make reusable

- Port 19 cohort scripts from /home/naomi/docs/cohort/
- Replace all hardcoded tokens and dotenv usage with os.environ
- Add pandas==3.0.1 dependency
- Add E501 to ruff ignore list for Discord message string content
- Make remove_resigned_members.py reusable (empty RESIGNED_IDS constant)
- Make update_roster_messages.py reusable (iterates all teams from JSON)
- Exclude 12 one-off/event-specific scripts as non-reusable

python/cohort/check_member_status.py

@@ -0,0 +1,49 @@
+#!/usr/bin/env python3
+"""Check if removed members are still in the Discord server."""
+
+import asyncio
+import os
+
+import aiohttp
+
+DISCORD_BOT_TOKEN = os.environ["DISCORD_BOT_TOKEN"]
+BASE_URL = "https://discord.com/api/v10"
+GUILD_ID = "1354624415861833870"
+
+SAMPLE_MEMBERS = [
+    "899092786802987069",
+    "1318882254365397032",
+    "799293680799711273",
+    "237793557992308736",
+]
+
+
+async def check_member(session: aiohttp.ClientSession, user_id: str) -> bool | None:
+    """Check if a member is in the server."""
+    url = f"{BASE_URL}/guilds/{GUILD_ID}/members/{user_id}"
+    headers = {"Authorization": f"Bot {DISCORD_BOT_TOKEN}"}
+
+    async with session.get(url, headers=headers) as resp:
+        if resp.status == 200:
+            data = await resp.json()
+            roles = data.get("roles", [])
+            print(f"✅ User {user_id} IS in server - has {len(roles)} roles: {roles}")
+            return True
+        if resp.status == 404:
+            print(f"❌ User {user_id} NOT in server (left or was kicked)")
+            return False
+        error = await resp.text()
+        print(f"⚠️  Error checking {user_id}: {resp.status} - {error}")
+        return None
+
+
+async def main() -> None:
+    """Check if sample members are still in the server."""
+    async with aiohttp.ClientSession() as session:
+        for user_id in SAMPLE_MEMBERS:
+            await check_member(session, user_id)
+            await asyncio.sleep(1)
+
+
+if __name__ == "__main__":
+    asyncio.run(main())