refactor: rename packages and files to use 'flash' prefix for consistency

flash-extensions/flash-ext-web-bundler/docs/README.md

@@ -0,0 +1,24 @@
+# flash-web-bundler
+
+`flash-web-bundler` integrates frontend tooling lifecycle into Flash with explicit, policy-driven behavior.
+
+## Quick Start
+
+```java
+FlashApp.create(8080)
+    .install(new WebBundlerExtension(
+        WebBundlerConfig.builder()
+            .webRoot(Path.of("web"))
+            .basePath("/")
+            .build()
+    ))
+    .start();
+```
+
+## Operating Model
+
+- Dev: orchestrates frontend process lifecycle and health checks.
+- Prod: serves prebuilt assets from `assetsSource` with ETag/cache/compression support.
+- Route precedence: backend first, SPA fallback second (`GET`/`HEAD`).
+
+See also: `asset-sources.md`.