fix: Fix CSV export, season filtering, and position matching in refactored services

Integration testing revealed three issues with the refactored service layer:

1. CSV Export Format
   - Nested team/sbaplayer dicts were being dumped as strings
   - Now flattens team to abbreviation, sbaplayer to ID
   - Matches original CSV format from pre-refactor code

2. Season=0 Filter
   - season=0 was filtering for WHERE season=0 (returns nothing)
   - Now correctly returns all seasons when season=0 or None
   - Affects 13,266 total players across all seasons

3. Generic Position "P"
   - pos=P returned no results (players have SP/RP/CP, not P)
   - Now expands P to match SP, RP, CP pitcher positions
   - Applied to both DB filtering and Python mock filtering

4. Roster Endpoint Enhancement
   - Added default /teams/{id}/roster endpoint (assumes 'current')
   - Existing /teams/{id}/roster/{which} endpoint unchanged

All changes maintain backward compatibility and pass integration tests.

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

app/routers_v3/teams.py

@@ -49,6 +49,17 @@ async def get_one_team(team_id: int):
     return TeamService.get_team(team_id)
 
 
+@router.get('/{team_id}/roster')
+@handle_db_errors
+@cache_result(ttl=30*60, key_prefix='team-roster')
+async def get_team_roster_default(
+    team_id: int,
+    sort: Optional[str] = None
+):
+    """Get team roster with IL lists (defaults to current season)."""
+    return TeamService.get_team_roster(team_id, 'current', sort=sort)
+
+
 @router.get('/{team_id}/roster/{which}')
 @handle_db_errors
 @cache_result(ttl=30*60, key_prefix='team-roster')

app/services/player_service.py

@@ -182,6 +182,13 @@ class PlayerService(BaseService):
 
                 if pos:
                     p_list = [x.upper() for x in pos]
+
+                    # Expand generic "P" to match all pitcher positions
+                    pitcher_positions = ['SP', 'RP', 'CP']
+                    if 'P' in p_list:
+                        p_list.remove('P')
+                        p_list.extend(pitcher_positions)
+
                     pos_conditions = (
                         (Player.pos_1 << p_list)
                         | (Player.pos_2 << p_list)
@@ -216,6 +223,13 @@ class PlayerService(BaseService):
                     return False
                 if pos:
                     p_list = [p.upper() for p in pos]
+
+                    # Expand generic "P" to match all pitcher positions
+                    pitcher_positions = ['SP', 'RP', 'CP']
+                    if 'P' in p_list:
+                        p_list.remove('P')
+                        p_list.extend(pitcher_positions)
+
                     player_pos = [
                         player.get(f"pos_{i}")
                         for i in range(1, 9)
@@ -547,13 +561,27 @@ class PlayerService(BaseService):
         if not players:
             return ""
 
-        # Build CSV from dict data (works with mocks)
+        # Flatten nested objects for CSV export
+        flattened_players = []
+        for player in players:
+            flat_player = player.copy()
 
+            # Flatten team object to just abbreviation
+            if isinstance(flat_player.get('team'), dict):
+                flat_player['team'] = flat_player['team'].get('abbrev', '')
+
+            # Flatten sbaplayer object to just ID
+            if isinstance(flat_player.get('sbaplayer'), dict):
+                flat_player['sbaplayer'] = flat_player['sbaplayer'].get('id', '')
+
+            flattened_players.append(flat_player)
+
+        # Build CSV from flattened data
         output = io.StringIO()
-        if players:
-            writer = csv.DictWriter(output, fieldnames=players[0].keys())
+        if flattened_players:
+            writer = csv.DictWriter(output, fieldnames=flattened_players[0].keys())
             writer.writeheader()
-            writer.writerows(players)
+            writer.writerows(flattened_players)
 
         return output.getvalue()
 
@@ -595,7 +623,9 @@ class RealPlayerRepository:
         self._model = model_class
 
     def select_season(self, season: int):
-        """Return query for season."""
+        """Return query for season. Season=0 or None returns all seasons."""
+        if season == 0 or season is None:
+            return self._model.select()
         return self._model.select().where(self._model.season == season)
 
     def get_by_id(self, player_id: int):