Link personal bests to their recorded matches

src/lib/server/db/index.ts

@@ -360,6 +360,10 @@ export function db(): Database.Database {
         assertSnapshotSchemeSafe(handle);
         migrateGameTelemetry(handle);
         migrateTable(handle, 'leaderboard_matches', [{ name: 'start_players', ddl: 'ALTER TABLE leaderboard_matches ADD COLUMN start_players INTEGER' }]);
+        migrateTable(handle, 'leaderboard_match_players', [
+            { name: 'first_observed_round', ddl: 'ALTER TABLE leaderboard_match_players ADD COLUMN first_observed_round INTEGER' },
+            { name: 'present_at_start', ddl: 'ALTER TABLE leaderboard_match_players ADD COLUMN present_at_start INTEGER' }
+        ]);
         backfillLeaderboard(handle);
         initializeFleetSettings(handle);
     } catch (err) {

src/lib/server/db/schema.sql

@@ -55,6 +55,8 @@ CREATE TABLE IF NOT EXISTS leaderboard_match_players (
     completed INTEGER NOT NULL DEFAULT 0,
     first_seen_at TEXT NOT NULL,
     last_seen_at TEXT NOT NULL,
+    first_observed_round INTEGER, -- null for legacy participation
+    present_at_start INTEGER, -- null for legacy participation; one only when first seen in game_start
     PRIMARY KEY (match_id, guid)
 );
 CREATE INDEX IF NOT EXISTS idx_leaderboard_player_matches ON leaderboard_match_players(guid, match_id);