chore: simplify style dedupe config

packages/@lwc/engine-server/src/__tests__/fixtures/style-dedupe-with-prefix/config.json

@@ -1,4 +1,4 @@
 {
     "entry": "x/parent",
-    "styleDedupePrefix": "island1"
+    "styleDedupe": "island1"
 }

packages/@lwc/ssr-compiler/src/__tests__/fixtures.spec.ts

@@ -32,7 +32,7 @@ interface FixtureConfig {
     };
 
     /** The string used to uniquely identify one set of dedupe IDs with multiple SSR islands */
-    styleDedupePrefix?: string;
+    styleDedupe?: string;
 }
 
 vi.mock('@lwc/ssr-runtime', async () => {
@@ -127,8 +127,7 @@ describe.concurrent('fixtures', () => {
                         'fixture-test',
                         module,
                         config?.props ?? {},
-                        config?.styleDedupePrefix ?? '',
-                        true,
+                        config?.styleDedupe ?? true,
                         SSR_MODE
                     )
                 );

packages/@lwc/ssr-runtime/src/render.ts

@@ -193,22 +193,26 @@ interface ComponentWithGenerateMarkup extends LightningElementConstructor {
 
 export class RenderContext {
     styleDedupeIsEnabled: boolean;
-    stylesheetToId = new WeakMap<Stylesheet, string>();
     styleDedupePrefix: string;
+    stylesheetToId = new WeakMap<Stylesheet, string>();
     nextId = 0;
 
-    constructor(styleDedupePrefix: string, styleDedupeIsEnabled: boolean) {
-        this.styleDedupeIsEnabled = styleDedupeIsEnabled;
-        this.styleDedupePrefix = styleDedupePrefix;
+    constructor(styleDedupe: string | boolean) {
+        if (styleDedupe || styleDedupe === '') {
+            this.styleDedupePrefix = typeof styleDedupe === 'string' ? styleDedupe : '';
+            this.styleDedupeIsEnabled = true;
+        } else {
+            this.styleDedupePrefix = '';
+            this.styleDedupeIsEnabled = false;
+        }
     }
 }
 
 export async function serverSideRenderComponent(
     tagName: string,
     Component: ComponentWithGenerateMarkup,
     props: Properties = {},
-    styleDedupePrefix = '',
-    styleDedupeIsEnabled = false,
+    styleDedupe: string | boolean = false,
     mode: CompilationMode = DEFAULT_SSR_MODE
 ): Promise<string> {
     if (typeof tagName !== 'string') {
@@ -222,7 +226,7 @@ export async function serverSideRenderComponent(
         markup += segment;
     };
 
-    emit.cxt = new RenderContext(styleDedupePrefix, styleDedupeIsEnabled);
+    emit.cxt = new RenderContext(styleDedupe);
 
     if (!generateMarkup) {
         // If a non-component is accidentally provided, render an empty template