feat: add Telegram gradient theme (DenverCoder1#742)

Author: ankddev

docs/themes.md

@@ -159,6 +159,7 @@ Note: Theme names provided are case-insensitive and any use of underscores will
 |       `dark-minimalist`       | ![image](https://github.com/DenverCoder1/github-readme-streak-stats/assets/77511070/11ba7899-1ad3-4c4b-880b-6f9e7c285f1b)  |
 |          `telegram`           |                 ![image](https://github.com/user-attachments/assets/59a5d9d5-8a2a-4916-aa46-a0a49a6f0372)                  |
 |            `taiga`            |                 ![image](https://github.com/user-attachments/assets/be4e961d-a13e-401a-90f8-f2b062a8c0f9)                  |
+|      `telegram-gradient`      |                 ![image](https://github.com/user-attachments/assets/985c3e04-a5dd-4cba-a66e-d43ad9668af0)                  |
 |          `microsoft`          |                 ![image](https://github.com/user-attachments/assets/4c2cce9d-90b5-4e38-8422-656c5a78b4d9)                  |
 |       `microsoft-dark`        |                 ![image](https://github.com/user-attachments/assets/a5918d7d-f568-4012-b06f-d9cfacaece04)                  |
 

src/themes.php

@@ -1965,6 +1965,19 @@
         "dates" => "#1F8F92",
         "excludeDaysLabel" => "#1F8F92",
     ],
+    "telegram-gradient" => [
+        "background" => "45,0088CC,179CDE",
+        "border" => "#FFFFFF",
+        "stroke" => "#FFFFFF",
+        "ring" => "#FFFFFF",
+        "fire" => "#FFFFFF",
+        "currStreakNum" => "#FFFFFF",
+        "sideNums" => "#FFFFFF",
+        "currStreakLabel" => "#FFFFFF",
+        "sideLabels" => "#FFFFFF",
+        "dates" => "#FFFFFF",
+        "excludeDaysLabel" => "#FFFFFF",
+    ],
     "microsoft" => [
         "background" => "#FFFFFF",
         "border" => "#737373",