Add DDL-based DB init and bootstrap

Add bootstrap entrypoint and migrate DB schema setup to SQL files. Introduces bootstrap.js, many data/ddl/*.sql files, and a new runDDL() in modules/database.js (exports pool and runDDL). Remove legacy modules/databaseGlobals.js. Update repositories and code to use database.pool.query calls. Bump package version and set main to bootstrap.js. Clean up server.js to remove inline DB/cert init (now handled by bootstrap). Overall: refactor DB initialization to run ordered SQL DDL files and centralize startup logic.

data/ddl/20_auto_assign_random_default_skin.sql

@@ -0,0 +1,23 @@
+DROP TRIGGER IF EXISTS auto_assign_random_default_skin;
+
+CREATE TRIGGER auto_assign_random_default_skin
+AFTER INSERT ON players
+FOR EACH ROW
+BEGIN
+    INSERT INTO playersSkins (playerUuid, assetHash, variant, isSelected)
+    SELECT 
+        NEW.uuid,
+        hash,
+        CASE 
+            WHEN hash = '4c7b0468044bfecacc43d00a3a69335a834b73937688292c20d3988cae58248d' THEN 'CLASSIC'
+            ELSE 'SLIM'
+        END,
+        1
+    FROM textures
+    WHERE hash IN (
+        '4c7b0468044bfecacc43d00a3a69335a834b73937688292c20d3988cae58248d',
+        'df8ed96c557d441a63e7b6a4a911ab84fa453b42fc2ae6b01c3e1b02e138168c'
+    )
+    ORDER BY RAND()
+    LIMIT 1;
+END;