[webpack5-localization-plugin] Streamline processing (#5095)

* [webpack5-localization-plugin] Streamline processing

* Fix formatting

* Fix variable

---------

Co-authored-by: David Michon <dmichon-msft@users.noreply.github.com>

Author: dmichon-msft

common/changes/@rushstack/webpack5-localization-plugin/localization-plugin-cache_2025-02-03-23-39.json

@@ -0,0 +1,10 @@
+{
+  "changes": [
+    {
+      "packageName": "@rushstack/webpack5-localization-plugin",
+      "comment": "Leverage webpack caching layer for localized and nonlocalized asset generation. Reduce unnecessary work.",
+      "type": "minor"
+    }
+  ],
+  "packageName": "@rushstack/webpack5-localization-plugin"
+}

common/reviews/api/webpack5-localization-plugin.api.md

@@ -125,8 +125,8 @@ export interface _IStringPlaceholder {
     locFilePath: string;
     stringName: string;
     suffix: string;
+    translations: ReadonlyMap<string, ReadonlyMap<string, string>>;
     value: string;
-    valuesByLocale: Map<string, string>;
 }
 
 // @public (undocumented)
@@ -147,8 +147,6 @@ export class LocalizationPlugin implements WebpackPluginInstance {
     getPlaceholder(localizedFileKey: string, stringName: string): _IStringPlaceholder | undefined;
     // @internal (undocumented)
     readonly _options: ILocalizationPluginOptions;
-    // (undocumented)
-    readonly stringKeys: Map<string, _IStringPlaceholder>;
 }
 
 // @public (undocumented)