VPR-62 feat(student): Add backend Career Selection code

.editorconfig

@@ -178,3 +178,9 @@ dotnet_diagnostic.CA1505.severity = none
 # ApiPaginationAttribute.OnActionExecuting always constructs the object and overwrites the action argument
 [web/Models/ApiPagination.cs]
 dotnet_diagnostic.S6964.severity = none
+
+# S6964: IsOther is bound as part of the save request but never trusted — ValidateSelectionAsync
+# re-reads it from the option table before the mapper consumes it, so a client value cannot
+# influence what is stored
+[web/Areas/Students/Models/CareerDropdownOption.cs]
+dotnet_diagnostic.S6964.severity = none

.gitignore

@@ -511,6 +511,9 @@ web/Areas/Effort/Scripts/Effort_Database_Schema_And_Data_LEGACY.txt
 # PhoneLists migration script outputs
 web/Areas/Personnel/Scripts/AnalysisOutput/
 
+# Career Selection migration script outputs
+web/Areas/Students/Scripts/AnalysisOutput/
+
 # Code-quality tool outputs (fallow cache + jscpd + ReSharper reports)
 .fallow/
 VueApp/.fallow/

.jscpd.json

@@ -6,7 +6,9 @@
         "**/coverage/**",
         "**/bin/**",
         "**/obj/**",
-        "**/Effort/Scripts/**"
+        "**/Effort/Scripts/**",
+        "**/Personnel/Scripts/**",
+        "**/Students/Scripts/**"
     ],
     "ignorePattern": [
         "^\\s*import\\s+.*from\\s+['\"][^'\"]+['\"]\\s*;?\\s*$"

test/Classes/Utilities/DbUpdateExceptionExtensionsTests.cs

@@ -52,4 +52,30 @@ public void IsDataRejection_IsFalse_WhenTheInnerExceptionIsNotFromSqlServer()
 
         Assert.False(ex.IsDataRejection());
     }
+
+    [Theory]
+    [InlineData(2601)] // duplicate key in a unique index
+    [InlineData(2627)] // unique or primary key constraint violation
+    public void IsUniqueKeyViolationNumber_IsTrue_ForUniqueKeyErrors(int number)
+    {
+        Assert.True(DbUpdateExceptionExtensions.IsUniqueKeyViolationNumber(number));
+    }
+
+    [Theory]
+    [InlineData(547)]  // foreign key - a retry against the winning row would fail the same way
+    [InlineData(8152)] // truncation - likewise
+    [InlineData(2628)]
+    [InlineData(1205)]
+    public void IsUniqueKeyViolationNumber_IsFalse_ForOtherErrors(int number)
+    {
+        Assert.False(DbUpdateExceptionExtensions.IsUniqueKeyViolationNumber(number));
+    }
+
+    [Fact]
+    public void IsUniqueKeyViolation_IsFalse_WhenTheInnerExceptionIsNotFromSqlServer()
+    {
+        var ex = new DbUpdateException("Something failed", new TimeoutException("The wait expired"));
+
+        Assert.False(ex.IsUniqueKeyViolation());
+    }
 }

test/Effort/ExcelHelperTests.cs → test/Classes/Utilities/ExcelHelperTests.cs

@@ -1,6 +1,6 @@
 using Viper.Classes.Utilities;
 
-namespace Viper.test.Effort;
+namespace Viper.test.Classes.Utilities;
 
 /// <summary>
 /// Unit tests for ExcelHelper utility methods.
@@ -33,6 +33,29 @@ public void SanitizeStringCell_PrefixesAtSign()
         Assert.Equal("'@SUM", ExcelHelper.SanitizeStringCell("@SUM"));
     }
 
+    [Theory]
+    [InlineData("\t=SUM(A1)")]
+    [InlineData("\r=SUM(A1)")]
+    [InlineData("\n+cmd")]
+    [InlineData("\r\n-calculation")]
+    [InlineData("   @SUM")]
+    [InlineData(" \t\r\n=HYPERLINK(\"x\")")]
+    public void SanitizeStringCell_PrefixesFormulaBehindLeadingWhitespace(string value)
+    {
+        Assert.Equal("'" + value, ExcelHelper.SanitizeStringCell(value));
+    }
+
+    [Theory]
+    [InlineData("  Normal text")]
+    [InlineData("\tIndented")]
+    [InlineData("\r\nSecond line")]
+    [InlineData("   ")]
+    [InlineData("Ends with =")]
+    public void SanitizeStringCell_LeavesNonFormulaTextUnchanged(string value)
+    {
+        Assert.Equal(value, ExcelHelper.SanitizeStringCell(value));
+    }
+
     [Fact]
     public void SanitizeStringCell_LeavesNormalTextUnchanged()
     {