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_member.py

@@ -18,9 +18,12 @@ import json
 import os
 import sys
 from datetime import datetime, timezone
+from pathlib import Path
 
 import aiohttp
 
+DATA_DIR = Path(__file__).parent.parent.parent / "data"
+
 DISCORD_BOT_TOKEN = os.environ["DISCORD_BOT_TOKEN"]
 DISCORD_API_BASE = "https://discord.com/api/v10"
 DISCORD_GUILD_ID = "692816967895220344"
@@ -71,7 +74,7 @@ class MemberRemover:
 
     def find_member_info(self) -> bool:
         """Find which team the member is on and their role."""
-        with open("team_assignments.json") as f:
+        with open(DATA_DIR / "team_assignments.json") as f:
             teams = json.load(f)
 
         for team in teams:
@@ -88,7 +91,7 @@ class MemberRemover:
 
     def remove_from_team_assignments(self) -> None:
         """Remove member from team_assignments.json."""
-        with open("team_assignments.json") as f:
+        with open(DATA_DIR / "team_assignments.json") as f:
             teams = json.load(f)
 
         for team in teams:
@@ -103,19 +106,19 @@ class MemberRemover:
                     f"✅ Removed from {team['name']} participants in team_assignments.json"
                 )
 
-        with open("team_assignments.json", "w") as f:
+        with open(DATA_DIR / "team_assignments.json", "w") as f:
             json.dump(teams, f, indent=2)
 
     def remove_from_discord_to_github(self) -> None:
         """Remove member from discord_to_github.json."""
-        with open("discord_to_github.json") as f:
+        with open(DATA_DIR / "discord_to_github.json") as f:
             mappings = json.load(f)
 
         if self.discord_id in mappings:
             self.github_username = mappings[self.discord_id]
             del mappings[self.discord_id]
 
-            with open("discord_to_github.json", "w") as f:
+            with open(DATA_DIR / "discord_to_github.json", "w") as f:
                 json.dump(mappings, f, indent=2)
 
             print(f"✅ Removed {self.github_username} from discord_to_github.json")
@@ -135,7 +138,7 @@ class MemberRemover:
 
     async def remove_discord_roles(self) -> None:
         """Remove Discord roles from the member."""
-        with open("team_message_ids.json") as f:
+        with open(DATA_DIR / "team_message_ids.json") as f:
             team_message_data = json.load(f)
 
         if self.team_name not in team_message_data: