refactor: make react hello example follow specs (#1233)

This PR will rewrite the `client-only` example into our official
`hello-react` example.

The `hello-react` example is much simpler than the previous
`client-only` and does only the things described in the hello example
specs.

## Caveats
I still have the `client-only` example in my local instance... I think
we can think about adding it in if there is a demand for more complex
sample applications

<!-- CURSOR_SUMMARY -->
---

> [!NOTE]
> **Low Risk**
> Low risk: changes are limited to example app code and CI workflows
that run example e2e tests; main SDK logic is untouched, but CI could
fail if the new workspace name or dependencies are misconfigured.
> 
> **Overview**
> Switches React example coverage from the old
`@internal/react-sdk-example-client-only` app to a new, spec-aligned
`hello-react` example, and updates both `react.yml` and
`react-nightly.yaml` to run its Playwright e2e tests.
> 
> Removes the `client-only` example from workspaces and replaces it with
`packages/sdk/react/examples/hello-react`, including new top-level
examples docs (`packages/sdk/react/examples/README.md`) and ignore
rules. The `hello-react` app is simplified (no context switching /
flag-key form) and its workspace now pins `@launchdarkly/react-sdk` to
`0.1.1` instead of using the monorepo `workspace:^` dependency.
> 
> <sup>Written by [Cursor
Bugbot](https://cursor.com/dashboard?tab=bugbot) for commit
8ead7b3. This will update automatically
on new commits. Configure
[here](https://cursor.com/dashboard?tab=bugbot).</sup>
<!-- /CURSOR_SUMMARY -->

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Author: joker23

.github/workflows/react-nightly.yaml

@@ -16,6 +16,6 @@ jobs:
           node-version: 24
       - uses: ./actions/run-example
         with:
-          workspace_name: '@internal/react-sdk-example-client-only'
+          workspace_name: '@internal/react-sdk-example-hello-react'
           aws_assume_role: ${{ vars.AWS_ROLE_ARN }}
-          before_test: 'yarn workspace @internal/react-sdk-example-client-only playwright install --with-deps chromium'
+          before_test: 'yarn workspace @internal/react-sdk-example-hello-react playwright install --with-deps chromium'

.github/workflows/react.yml

@@ -92,9 +92,9 @@ jobs:
           node-version: 24
       - uses: ./actions/run-example
         with:
-          workspace_name: '@internal/react-sdk-example-client-only'
+          workspace_name: '@internal/react-sdk-example-hello-react'
           aws_assume_role: ${{ vars.AWS_ROLE_ARN }}
-          before_test: 'yarn workspace @internal/react-sdk-example-client-only playwright install --with-deps chromium'
+          before_test: 'yarn workspace @internal/react-sdk-example-hello-react playwright install --with-deps chromium'
 
   run-server-only-example:
     runs-on: ubuntu-latest

actions/run-example/action.yml

@@ -3,7 +3,7 @@
 name: Run Example App
 inputs:
   workspace_name:
-    description: 'Yarn workspace name of the example app, e.g. @internal/react-sdk-example-client-only'
+    description: 'Yarn workspace name of the example app'
     required: true
   aws_assume_role:
     description: 'AWS OIDC role ARN used to fetch secrets from SSM'

package.json

@@ -20,7 +20,7 @@
     "packages/sdk/fastly/example",
     "packages/sdk/react",
     "packages/sdk/react/contract-tests",
-    "packages/sdk/react/examples/client-only",
+    "packages/sdk/react/examples/hello-react",
     "packages/sdk/react/examples/server-only",
     "packages/sdk/react-native",
     "packages/sdk/react-native/example",

packages/sdk/react/examples/.gitignore

@@ -0,0 +1,3 @@
+# Have a way to create temporary examples
+# for testing and development purposes
+temp-*

packages/sdk/react/examples/README.md

@@ -0,0 +1,8 @@
+# LaunchDarkly React SDK — Examples
+
+This directory contains example applications demonstrating the LaunchDarkly React SDK.
+
+| Example | Description |
+|---------|-------------|
+| [hello-react](./hello-react/) | Minimal Vite + React app that evaluates a boolean feature flag and displays the result with real-time updates. This is the recommended starting point. |
+| [server-only](./server-only/) | Next.js App Router example demonstrating server-side flag evaluation with React Server Components. |

packages/sdk/react/examples/client-only/README.md

@@ -15,6 +15,7 @@
 .env.development.local
 .env.test.local
 .env.production.local
+.env
 
 npm-debug.log*
 yarn-debug.log*