[Docs][Content][UI] - JWT docs and JWT component (#905)

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Adds JWT docs and JWT viewer component to docs

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<!-- RECURSEML_SUMMARY:START -->
## High-level PR Summary
This PR adds comprehensive JWT (JSON Web Token) documentation and an
interactive JWT viewer component to the Stack Auth documentation. The
main additions are a new documentation page explaining JWT concepts,
structure, and usage within Stack Auth, along with a React component
that allows users to decode and inspect JWT tokens. The JWT viewer can
automatically load the current user's session token if they are signed
in, or accept manually pasted tokens. The documentation provides
examples of both client-side and server-side JWT usage, security
considerations, troubleshooting guidance, and best practices. The PR
also includes necessary updates to metadata files and component exports
to integrate the new content into the documentation platform.

⏱️ Estimated Review Time: 15-30 minutes

<details>
<summary>💡 Review Order Suggestion</summary>

| Order | File Path |
|-------|-----------|
| 1 | `docs/templates/concepts/jwt.mdx` |
| 2 | `docs/src/components/mdx/jwt-viewer.tsx` |
| 3 | `docs/docs-platform.yml` |
| 4 | `docs/src/components/mdx/index.ts` |
| 5 | `docs/src/mdx-components.tsx` |
| 6 | `docs/templates/meta.json` |
| 7 | `docs/templates-python/meta.json` |
</details>



<!-- RECURSEML_SUMMARY:END -->
<!-- ELLIPSIS_HIDDEN -->


----

> [!IMPORTANT]
> Adds a new JWT concepts page and an interactive `JWTViewer` component,
integrating it into MDX and navigation, with `jose` added for decoding.
> 
>   - **Docs**:
> - Add `concepts/jwt.mdx` with JWT structure, claims, examples,
verification, security, and best practices.
> - Include JWT page in navigation: `docs-platform.yml`,
`templates/meta.json`, and Python `templates-python/meta.json`.
>   - **UI Component**:
> - Add `JWTViewer` in `docs/src/components/mdx/jwt-viewer.tsx` to
decode JWTs (header, payload, signature), show time-based indicators,
and load current user token via `useUser()`.
> - Export and register in MDX: `docs/src/components/mdx/index.ts`,
`docs/src/mdx-components.tsx`.
>   - **Dependencies**:
>     - Add `jose` to `docs/package.json` (lockfile updated).
> 
> <sup>This description was created by </sup>[<img alt="Ellipsis"
src="https://img.shields.io/badge/Ellipsis-blue?color=175173">](https://www.ellipsis.dev?ref=stack-auth%2Fstack-auth&utm_source=github&utm_medium=referral)<sup>
for f25e369. You can
[customize](https://app.ellipsis.dev/stack-auth/settings/summaries) this
summary. It will automatically update as commits are pushed.</sup>

----


<!-- ELLIPSIS_HIDDEN -->

<!-- RECURSEML_ANALYSIS:START -->
## Review by RecurseML

_🔍 Review performed on
[ad34cfe..a135bbd](ad34cfe...a135bbdd77d0bc385dc660516029897887502dec)_

✨ No bugs found, your code is sparkling clean

<details>
<summary>✅ Files analyzed, no issues (3)</summary>

  • `docs/src/components/mdx/jwt-viewer.tsx`
  • `docs/src/mdx-components.tsx`
  • `docs/src/components/mdx/index.ts`
</details>

<details>
<summary>⏭️ Files skipped (trigger manually) (4)</summary>

| &nbsp; Locations &nbsp; | &nbsp; Trigger Analysis &nbsp; |
|-----------|:------------------:|
`docs/docs-platform.yml` |
[![Analyze](https://img.shields.io/badge/Analyze-238636?style=plastic)](https://squash-322339097191.europe-west3.run.app/interactive/4da4b078574a59406b7d9b8bcb847990999591df6cc54c74e830e62cf092a96c/?repo_owner=stack-auth&repo_name=stack-auth&pr_number=905)
`docs/templates-python/meta.json` |
[![Analyze](https://img.shields.io/badge/Analyze-238636?style=plastic)](https://squash-322339097191.europe-west3.run.app/interactive/36697f876fcf97a260cb8c86fda245d0d9ee5c722d28419599524fd4b61accc5/?repo_owner=stack-auth&repo_name=stack-auth&pr_number=905)
`docs/templates/concepts/jwt.mdx` |
[![Analyze](https://img.shields.io/badge/Analyze-238636?style=plastic)](https://squash-322339097191.europe-west3.run.app/interactive/d6cbe744221c23fdd0d6abe405c84027eefc3c6a3a1647e0a88b5d0a5d5fdc8e/?repo_owner=stack-auth&repo_name=stack-auth&pr_number=905)
`docs/templates/meta.json` |
[![Analyze](https://img.shields.io/badge/Analyze-238636?style=plastic)](https://squash-322339097191.europe-west3.run.app/interactive/49fb1d30374f5d38349d3b118155d87ace27b836040357dfcfefa1807a1ed6dd/?repo_owner=stack-auth&repo_name=stack-auth&pr_number=905)
</details>

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<!-- RECURSEML_ANALYSIS:END -->

<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit

* **New Features**
* Interactive JWT Viewer in the docs: paste or auto-load a token to
inspect header, payload, signature with live decoding, validity/time
indicators, per-field copy controls, and "load my token".

* **Documentation**
* New "JWT" concept page covering structure, claims, examples,
client/server/manual usage, security, troubleshooting, and best
practices.
* JWT page added to site navigation and enabled across Next, React, JS,
and Python docs.

* **Chores**
  * Added runtime dependency to support JWT decoding in the docs.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->

<!-- CURSOR_SUMMARY -->
---

> [!NOTE]
> Adds a new JWT concepts page and an interactive `JWTViewer` component,
integrating it into MDX and navigation, with `jose` added for decoding.
> 
> - **Docs**:
> - Add `concepts/jwt.mdx` with JWT structure, claims, examples,
verification, security, and best practices.
> - Include JWT page in navigation: `docs-platform.yml`,
`templates/meta.json`, and Python `templates-python/meta.json`.
> - **UI Component**:
> - Add `JWTViewer` in `docs/src/components/mdx/jwt-viewer.tsx` to
decode JWTs (header, payload, signature), show time-based indicators,
and load current user token via `useUser()`.
> - Export and register in MDX: `docs/src/components/mdx/index.ts`,
`docs/src/mdx-components.tsx`.
> - **Dependencies**:
>   - Add `jose` to `docs/package.json` (lockfile updated).
> 
> <sup>Written by [Cursor
Bugbot](https://cursor.com/dashboard?tab=bugbot) for commit
837fffb. This will update automatically
on new commits. Configure
[here](https://cursor.com/dashboard?tab=bugbot).</sup>
<!-- /CURSOR_SUMMARY -->

---------

Co-authored-by: Konsti Wohlwend <n2d4xc@gmail.com>

Author: madster456

docs/docs-platform.yml

@@ -110,6 +110,9 @@ pages:
 
   - path: concepts/backend-integration.mdx
     platforms: ["next", "react", "js", "python"]
+
+  - path: concepts/jwt.mdx
+    platforms: ["next", "react", "js", "python"]
 
   - path: concepts/emails.mdx
     platforms: ["next", "react", "js"]  # No Python (server-side email functionality)

docs/package.json

@@ -40,6 +40,7 @@
     "fumadocs-openapi": "^8.1.12",
     "fumadocs-typescript": "^4.0.5",
     "fumadocs-ui": "15.3.3",
+    "jose": "^6.1.0",
     "js-yaml": "^4.1.0",
     "lucide-react": "^0.511.0",
     "mermaid": "^11.6.0",

docs/src/components/mdx/index.ts

@@ -2,6 +2,7 @@ export { Card } from './card';
 export { CardGroup } from './card-group';
 export { DynamicCodeblock } from './dynamic-code-block';
 export { Info } from './info';
+export { JWTViewer } from './jwt-viewer';
 export { StackContainer } from './stack-container';