fix(nextjs): Use value injection loader on instrumentation-client.ts|js

packages/nextjs/src/config/webpack.ts

@@ -744,7 +744,7 @@ function addValueInjectionLoader(
     });
   } else {
     newConfig.module.rules.push({
-      test: /sentry\.client\.config\.(jsx?|tsx?)/,
+      test: /(?:sentry\.client\.config\.(jsx?|tsx?)|(?:src[\\/])?instrumentation-client\.(js|ts))$/,
       use: [
         {
           loader: path.resolve(__dirname, 'loaders/valueInjectionLoader.js'),

packages/nextjs/test/config/loaders.test.ts

@@ -240,7 +240,7 @@ describe('webpack loaders', () => {
       });
 
       expect(finalWebpackConfig.module.rules).toContainEqual({
-        test: /sentry\.client\.config\.(jsx?|tsx?)/,
+        test: /(?:sentry\.client\.config\.(jsx?|tsx?)|(?:src[\\/])?instrumentation-client\.(js|ts))$/,
         use: [
           {
             loader: expect.stringMatching(/valueInjectionLoader\.js$/),

packages/nextjs/test/config/valueInjectionLoader.test.ts

@@ -35,6 +35,70 @@ describe('valueInjectionLoader', () => {
     expect(result).toMatch(';globalThis["foo"] = "bar";');
   });
 
+  it('should work with instrumentation-client.js files', () => {
+    const instrumentationLoaderThis = {
+      ...loaderThis,
+      resourcePath: './instrumentation-client.js',
+    };
+
+    const userCode = `
+      import * as Sentry from '@sentry/nextjs';
+      Sentry.init();
+    `;
+
+    const result = valueInjectionLoader.call(instrumentationLoaderThis, userCode);
+
+    expect(result).toMatch(';globalThis["foo"] = "bar";');
+  });
+
+  it('should work with instrumentation-client.ts files', () => {
+    const instrumentationLoaderThis = {
+      ...loaderThis,
+      resourcePath: './instrumentation-client.ts',
+    };
+
+    const userCode = `
+      import * as Sentry from '@sentry/nextjs';
+      Sentry.init();
+    `;
+
+    const result = valueInjectionLoader.call(instrumentationLoaderThis, userCode);
+
+    expect(result).toMatch(';globalThis["foo"] = "bar";');
+  });
+
+  it('should work with src/instrumentation-client.js files', () => {
+    const instrumentationLoaderThis = {
+      ...loaderThis,
+      resourcePath: './src/instrumentation-client.js',
+    };
+
+    const userCode = `
+      import * as Sentry from '@sentry/nextjs';
+      Sentry.init();
+    `;
+
+    const result = valueInjectionLoader.call(instrumentationLoaderThis, userCode);
+
+    expect(result).toMatch(';globalThis["foo"] = "bar";');
+  });
+
+  it('should work with src/instrumentation-client.ts files', () => {
+    const instrumentationLoaderThis = {
+      ...loaderThis,
+      resourcePath: './src/instrumentation-client.ts',
+    };
+
+    const userCode = `
+      import * as Sentry from '@sentry/nextjs';
+      Sentry.init();
+    `;
+
+    const result = valueInjectionLoader.call(instrumentationLoaderThis, userCode);
+
+    expect(result).toMatch(';globalThis["foo"] = "bar";');
+  });
+
   it('should correctly insert values with directive', () => {
     const userCode = `
       "use client"