Added the release notes MD file and corresponding node entry in the TOC.html file

Author: DeepakRajSundar

Flutter/Release-notes/v31.2.18.md

@@ -0,0 +1,44 @@
+---
+title: Essential Studio® for Flutter Release Notes - v31.2.18
+description: Learn here about the controls in the Essential Studio® for Flutter Weekly Nuget Release - Release Notes - v31.2.18
+platform: flutter
+documentation: ug
+---
+
+# Essential Studio® for Flutter - v31.2.18 Release Notes
+
+{% include release-info.html date="December 09, 2025"  version="v31.2.18" passed="34953" failed="0" %}
+
+{% directory path: _includes/release-notes/v31.2.18 %}
+
+{% include {{file.url}} %}
+
+{% enddirectory %}
+
+## Test Results
+
+| Component Name | Test Cases | Passed | Failed | Remarks |
+|---------------|------------|--------|--------|---------|
+| AI AssistView | 171 | 171 | 0 | All Passed |
+| Barcode Generator | 522 | 522 | 0 | All Passed |
+| Calendar | 1424 | 1424 | 0 | All Passed |
+| Cartesian Chart | 15472 | 15472 | 0 | All Passed |
+| Chat | 59 | 59 | 0 | All Passed |
+| Circular Chart | 544 | 544 | 0 | All Passed |
+| DataGrid | 5739 | 5739 | 0 | All Passed |
+| DateRangepicker | 635 | 635 | 0 | All Passed |
+| Excel Library | 762 | 762 | 0 | All Passed |
+| Funnel Chart | 224 | 224 | 0 | All Passed |
+| Linear gauge | 1293 | 1293 | 0 | All Passed |
+| Maps | 427 | 427 | 0 | All Passed |
+| PDF Library | 2065 | 2065 | 0 | All Passed |
+| Pyramid Chart | 223 | 223 | 0 | All Passed |
+| Radial Gauge | 3124 | 3124 | 0 | All Passed |
+| Range selector | 331 | 331 | 0 | All Passed |
+| Range Slider | 583 | 583 | 0 | All Passed |
+| Slider | 729 | 729 | 0 | All Passed |
+| Spark Area Chart | 130 | 130 | 0 | All Passed |
+| Spark Bar Chart | 90 | 90 | 0 | All Passed |
+| Spark Line Chart | 128 | 128 | 0 | All Passed |
+| Spark WinLoss Chart | 80 | 80 | 0 | All Passed |
+| Treemap | 198 | 198 | 0 | All Passed |