feat: Enhance Gantt chart functionality with task filtering and styling improvements

.vscode/ftp-kr.sync.cache.json

@@ -139,8 +139,8 @@
           },
           "class.Tasks.php": {
             "type": "-",
-            "size": 18282,
-            "lmtime": 1744416198811,
+            "size": 18381,
+            "lmtime": 1744445308848,
             "modified": false
           },
           "class.Users.php": {
@@ -297,14 +297,14 @@
         "Simple-Gant-master": {
           "frappe-gantt.css": {
             "type": "-",
-            "size": 4631,
-            "lmtime": 1744416274241,
+            "size": 4756,
+            "lmtime": 1744445361651,
             "modified": false
           },
           "frappe-gantt.js": {
             "type": "-",
-            "size": 78780,
-            "lmtime": 1744416131313,
+            "size": 78713,
+            "lmtime": 1744445195672,
             "modified": false
           },
           "frappe-gantt.js.map": {
@@ -374,8 +374,8 @@
           },
           "main_view.php": {
             "type": "-",
-            "size": 32482,
-            "lmtime": 1744416116971,
+            "size": 31686,
+            "lmtime": 1744443300056,
             "modified": false
           },
           "task_edit.php": {