Add Effect v4 support, Fast Refresh tooling, and revamped docs (#56)

## Summary

- Add `effect-fc-next`, a React 19 integration targeting Effect v4 beta.
- Introduce component lifecycles, scoped resources, queries, mutations, forms, lenses, views, and refreshable components.
- Add `@effect-view/vite-plugin` for Vite Fast Refresh support.
- Add an Effect v4 example application covering the new APIs.
- Expand test coverage for both the existing and next-generation packages.
- Replace the starter Docusaurus content with complete Effect View documentation while preserving the Effect v3 docs as a versioned snapshot.
- Update the landing page, navigation, package scripts, and build output.
- Extend CI with linting, tests, package builds, Docker builds, and container publishing.

## Validation

- `bun lint:tsc`
- `bun lint:biome`
- `bun test`
- `bun run build`
- `bun pack`
- Docker image build

---------

Co-authored-by: Julien Valverdé <julien.valverde@mailo.com>
Reviewed-on: Thilawyn/effect-fc#56

packages/vite-plugin/README.md

@@ -0,0 +1,41 @@
+# `@effect-view/vite-plugin`
+
+Experimental Vite Fast Refresh support for Effect View components.
+
+```ts
+import { effectViewPlugin } from "@effect-view/vite-plugin"
+import react from "@vitejs/plugin-react"
+import { defineConfig } from "vite"
+
+export default defineConfig({
+    plugins: [
+        effectViewPlugin(),
+        react(),
+    ],
+})
+```
+
+The plugin recognizes `Component.make` and `Component.makeUntraced`
+definitions imported from `effect-fc-next`. The legacy `effect-fc` package is
+not supported. `effect-fc-next` owns the bundler-neutral refresh cell protocol;
+this package is the Vite adapter that retains those cells in HMR data. The
+plugin assigns stable development IDs and self-accepts successfully
+instrumented modules.
+
+The adapter-facing protocol is exported from `effect-fc-next/Refreshable`.
+
+Renaming or removing an instrumented View invalidates the module upward instead
+of leaving a stale mounted descriptor.
+
+React state is retained when the ordered hook signature is unchanged. Adding,
+removing, or changing a hook call resets the Effect View implementation. Add
+`// @refresh reset` to a module to reset its Views on every update.
+
+## Current limitations
+
+- Definitions must be top-level variable, class, or default-export
+  declarations.
+- Hook signature analysis is conservative and based on `useX` call syntax.
+- Changing a descriptor's trait pipeline during a refresh is not guaranteed to
+  preserve state.
+- Source maps for the injected transform are not generated yet.