docs: add data file documentation and fix data path resolution

All Python cohort scripts now use DATA_DIR = Path(__file__).parent.parent.parent / "data"
to correctly resolve the repo-root data/ directory regardless of the working directory
set by run.sh. All TypeScript scripts have expanded JSDoc headers documenting data file
requirements and environment variables.

python/cohort/remove_discord_roles.py

@@ -1,5 +1,15 @@
 #!/usr/bin/env python3
-"""Remove cohort and team roles from inactive Discord members."""
+"""Remove the Cohort and team-specific Discord roles from a list of members.
+
+Update INACTIVE_MEMBERS and MEMBER_TO_TEAM before running to target the correct
+members. Removes both the cohort-wide role and the member's team role.
+
+Data files (place in data/):
+  - None (member IDs and team mappings are defined as constants in the script)
+
+Env vars:
+  - DISCORD_BOT_TOKEN  Bot token for the Discord API
+"""
 
 import asyncio
 import os