Remove version comparison logic and fix diagnostic message ordering

Co-authored-by: RyanCavanaugh <6685088+RyanCavanaugh@users.noreply.github.com>

Author: Copilot

src/compiler/checker.ts

@@ -48001,39 +48001,28 @@ export function createTypeChecker(host: TypeCheckerHost): TypeChecker {
                     const pos = getNonModifierTokenPosOfNode(node);
                     const span = getSpanOfTokenAtPosition(sourceFile, pos);
 
-                    // Check if we should generate an error (TS 6.0+) or suggestion (older versions)
-                    const currentVersion = new Version(versionMajorMinor);
-                    const errorVersion = new Version("6.0");
-                    const shouldError = currentVersion.compareTo(errorVersion) >= Comparison.EqualTo;
-
-                    // Check if ignoreDeprecations should suppress this error
-                    let shouldSuppress = false;
-                    if (shouldError && compilerOptions.ignoreDeprecations) {
-                        // Only valid ignoreDeprecations values: "5.0" and "6.0"
-                        if (compilerOptions.ignoreDeprecations === "6.0") {
-                            shouldSuppress = true;
-                        }
-                    }
-
-                    if (shouldError && !shouldSuppress) {
-                        // In TypeScript 6.0+, this is an error unless suppressed by ignoreDeprecations
-                        const errorDiagnostic = createFileDiagnostic(
-                            sourceFile,
-                            span.start,
-                            span.length,
-                            Diagnostics.The_module_keyword_is_not_allowed_for_namespace_declarations_Use_the_namespace_keyword_instead,
-                        );
-                        diagnostics.add(errorDiagnostic);
-                    }
-                    else {
-                        // In older versions or when suppressed, keep as suggestion
-                        const suggestionDiagnostic = createFileDiagnostic(
-                            sourceFile,
-                            span.start,
-                            span.length,
-                            Diagnostics.A_namespace_declaration_should_not_be_declared_using_the_module_keyword_Please_use_the_namespace_keyword_instead,
-                        );
-                        suggestionDiagnostics.add(suggestionDiagnostic);
+                    // Check if ignoreDeprecations should suppress this error
+                    const shouldSuppress = compilerOptions.ignoreDeprecations === "6.0";
+
+                    if (!shouldSuppress) {
+                        // Generate error for module keyword usage in namespace declarations
+                        const errorDiagnostic = createFileDiagnostic(
+                            sourceFile,
+                            span.start,
+                            span.length,
+                            Diagnostics.The_module_keyword_is_not_allowed_for_namespace_declarations_Use_the_namespace_keyword_instead,
+                        );
+                        diagnostics.add(errorDiagnostic);
+                    }
+                    else {
+                        // When suppressed by ignoreDeprecations, keep as suggestion
+                        const suggestionDiagnostic = createFileDiagnostic(
+                            sourceFile,
+                            span.start,
+                            span.length,
+                            Diagnostics.A_namespace_declaration_should_not_be_declared_using_the_module_keyword_Please_use_the_namespace_keyword_instead,
+                        );
+                        suggestionDiagnostics.add(suggestionDiagnostic);
                     }
                 }
             }

src/compiler/diagnosticMessages.json

@@ -1820,15 +1820,11 @@
         "category": "Error",
         "code": 1539
     },
-    "A 'namespace' declaration should not be declared using the 'module' keyword. Please use the 'namespace' keyword instead.": {
-        "category": "Suggestion",
-        "code": 1540,
-        "reportsDeprecated": true
-    },
-    "The 'module' keyword is not allowed for namespace declarations. Use the 'namespace' keyword instead.": {
-        "category": "Error",
-        "code": 1547
-    },
+    "A 'namespace' declaration should not be declared using the 'module' keyword. Please use the 'namespace' keyword instead.": {
+        "category": "Suggestion",
+        "code": 1540,
+        "reportsDeprecated": true
+    },
     "Type-only import of an ECMAScript module from a CommonJS module must have a 'resolution-mode' attribute.": {
         "category": "Error",
         "code": 1541
@@ -1849,11 +1845,15 @@
         "category": "Error",
         "code": 1545
     },
-    "'await using' declarations are not allowed in ambient contexts.": {
-        "category": "Error",
-        "code": 1546
-    },
-
+    "'await using' declarations are not allowed in ambient contexts.": {
+        "category": "Error",
+        "code": 1546
+    },
+    "The 'module' keyword is not allowed for namespace declarations. Use the 'namespace' keyword instead.": {
+        "category": "Error",
+        "code": 1547
+    },
+
     "The types of '{0}' are incompatible between these types.": {
         "category": "Error",
         "code": 2200