feat(db): prepared add and remove function

src/Service/ContributionStore.php

@@ -25,11 +25,35 @@ class ContributionStore {
         $this->pdo->exec('
             CREATE TABLE IF NOT EXISTS contributions (
                 provider TEXT NOT NULL,
-                date     TEXT NOT NULL,
+                date     INTEGER NOT NULL,
                 count    INTEGER NOT NULL CHECK (count >= 0),
                 PRIMARY KEY (provider, date)
             ) WITHOUT ROWID, STRICT
         ');
     }
 
+    public function add(string $provider, int $unixtime, int $count):void{
+       $stmt = $this->pdo->prepare('
+            INSERT INTO contributions (
+                provider, date, count
+            )
+            VALUES(
+            ?,?,?
+            )
+        ');
+        $stmt->execute([$provider,$unixtime,$count]);
+    }
+
+    public function remove(string $provider, int $unixtime):void{
+         $stmt = $this->pdo->prepare('
+            DELETE contributions
+            WHERE provider LIKE ? and date = ?
+        ');
+        $stmt->execute([$provider,$unixtime]);
+    }
+
+    public function all():void{
+
+    }
+    
 }