docs: add Jira Data Center integration setup guide (ext-377) (#3744)

# Jira Data Center Integration Documentation

This PR adds comprehensive documentation for the Jira Data Center
integration, including a detailed setup guide for creating and
configuring OAuth 2.0 credentials.

## Changes
- Added complete setup guide with step-by-step instructions
- Updated access requirements section
- Reformatted useful links into a table for better readability
- Added common OAuth scopes section
- Enhanced API gotchas section with important considerations

## References
- [Jira Data Center
Documentation](https://confluence.atlassian.com/enterprise/jira-data-center-documentation-668468332.html)
- [Configure an Incoming
Link](https://confluence.atlassian.com/adminjiraserver/configure-an-incoming-link-1115659067.html)
- [Jira OAuth 2.0 Provider
API](https://confluence.atlassian.com/adminjiraserver/jira-oauth-2-0-provider-api-1115659070.html)
- [OAuth 2.0 Provider System
Properties](https://confluence.atlassian.com/adminjiraserver/oauth-2-0-provider-system-properties-1115659073.html)

Link to Devin run:
https://app.devin.ai/sessions/94f14c04f0bf4a7bb75ab740686940de
Requested by: khaliq@nango.dev
<!-- Summary by @propel-code-bot -->

---

This PR replaces placeholder and outdated Jira Data Center integration
documentation with a detailed, step-by-step setup guide. It introduces
instructions for obtaining OAuth 2.0 credentials, configures proper
access requirements, streamlines useful links and scope documentation,
and enhances the overall user experience through improved formatting and
guidance.

**Key Changes:**
• Replaced placeholder setup content with a full step-by-step OAuth 2.0
integration guide using Steps/Step components
• Updated and clarified the 'Access requirements' table (now with
precise conditions and comments)
• Converted the 'Useful links' section from table to list and refreshed
external references
• Added a 'Common Scopes' section linking directly to Atlassian
documentation
• Simplified 'API gotchas' by removing direct implementation details per
review feedback

**Affected Areas:**
• docs-v2/integrations/all/jira-data-center.mdx

*This summary was automatically generated by @propel-code-bot*

---------

Co-authored-by: Devin AI <158243242+devin-ai-integration[bot]@users.noreply.github.com>
Co-authored-by: khaliq@nango.dev <khaliq@nango.dev>
Co-authored-by: lordsarcastic <adeoti.15.jude@gmail.com>
Co-authored-by: Khaliq <khaliqgant@gmail.com>

Author: 3 people

docs-v2/integrations/all/jira-data-center.mdx

@@ -14,20 +14,74 @@ import PreBuiltUseCases from "/snippets/generated/jira-data-center/PreBuiltUseCa
 ## Access requirements
 | Pre-Requisites | Status | Comment|
 | - | - | - |
-| Paid dev account | ❓ |  |
-| Paid test account | ❓ |  |
-| Partnership | ❓ | |
-| App review | ❓ |  |
-| Security audit | ❓ | |
+| Paid dev account | ⚠️ Conditional | Jira Data Center requires a license. You can [start a free trial](https://www.atlassian.com/software/jira/data-center/free-trial) for development. |
+| Paid test account | ⚠️ Conditional | Same as above. |
+| Partnership | ✅ Not required | |
+| App review | ✅ Not required | |
+| Security audit | ✅ Not required | |
 
 
 ## Setup guide
 
-_No setup guide yet._
+<Steps>
+  <Step title="Set up Jira Data Center">
+    1. Ensure you have a running Jira Data Center instance. If not, you can:
+       - [Start a free trial](https://www.atlassian.com/software/jira/data-center/free-trial)
+       - [Install Jira Data Center](https://confluence.atlassian.com/adminjiraserver/installing-jira-data-center-938846870.html)
+    2. Make sure you have administrator privileges on your Jira Data Center instance.
+  </Step>
+  <Step title="Create an incoming link">
+    1. Log in to your Jira Data Center instance as an administrator.
+    2. Navigate to **Administration** > **Applications** > **Application links**.
+    3. Select **Create link**.
+    4. Select **External application** and then choose **Incoming** as the direction.
+    5. Fill in the details as described in the sections below.
+  </Step>
+  <Step title="Provide application details">
+    In the application details section:
 
-<Tip>Need help getting started? Get help in the [community](https://nango.dev/slack).</Tip>
+    1. Enter a descriptive name for your application.
+    2. For the **Redirect URL**, enter `https://api.nango.dev/oauth/callback`.
+
+    Note: This is the URL where users will be redirected after authorizing your application.
+  </Step>
+  <Step title="Configure application permissions">
+    Select the appropriate permission scopes for your integration:
+
+    - **READ**: View projects and issues the user can view, including related items like dashboards, filters, attachments, or comments.
+    - **WRITE**: Create, update, and delete projects and issues the user can change, including related items.
+    - **ADMIN**: Perform most administrative functions on the entire Jira instance.
+    - **SYSTEM_ADMIN**: Perform all administrative functions on the entire Jira instance.
 
-<Note>Contribute improvements to the setup guide by [editing this page](https://github.com/nangohq/nango/tree/master/docs-v2/integrations/all/jira-data-center.mdx)</Note>
+    Note: Choose only the scopes your application needs. Higher-level scopes automatically include lower-level ones (e.g., WRITE includes READ).
+  </Step>
+  <Step title="Obtain OAuth credentials">
+    1. After creating the incoming link, you'll receive your OAuth credentials:
+       - **Client ID**: The identifier for your application
+       - **Client Secret**: The secret key for your application
+
+    2. Store these credentials securely as you'll need them to configure your integration in Nango.
+  </Step>
+  <Step title="Configure your integration in Nango">
+    When setting up your Jira Data Center integration in Nango:
+
+    - Use your **Client ID** and **Client Secret** from the previous step
+    - For the authorization URL, use: `https://[your-jira-instance]/rest/oauth2/latest/authorize`
+    - For the token URL, use: `https://[your-jira-instance]/rest/oauth2/latest/token`
+    - Replace `[your-jira-instance]` with your actual Jira Data Center instance URL
+  </Step>
+  <Step title="Test the OAuth flow">
+    1. After configuring your integration in Nango, test the OAuth flow to ensure it works correctly.
+    2. The authorization flow will redirect users to Jira where they can approve access to their account.
+    3. After approval, users will be redirected back to your application with an authorization code.
+    4. This code will be exchanged for access and refresh tokens.
+  </Step>
+  <Step title="Next">
+    Follow the [_Quickstart_](/getting-started/quickstart).
+  </Step>
+</Steps>
+
+<Tip>Need help getting started? Get help in the [community](https://nango.dev/slack).</Tip>
 
 
 ## Useful links
@@ -39,7 +93,10 @@ _No setup guide yet._
 
 <Note>Contribute useful links by [editing this page](https://github.com/nangohq/nango/tree/master/docs-v2/integrations/all/jira-data-center.mdx)</Note>
 
+## Common Scopes
+The list of scopes supported by the Jira Data Center API can be found in the [Provider API scopes documentation](https://confluence.atlassian.com/adminjiraserver/jira-oauth-2-0-provider-api-1115659070.html#JiraOAuth2.0providerAPI-scopes)
+
+
 ## API gotchas
--  Jira Data Center enforce HTTPS for the base URL of production environments. You can use insecure URIs and base URLs for staging or development environments by enabling the relevant [system properties](https://confluence.atlassian.com/adminjiraserver/oauth-2-0-provider-system-properties-1115659073.html)
 
-<Note>Contribute API gotchas by [editing this page](https://github.com/nangohq/nango/tree/master/docs-v2/integrations/all/jira-data-center.mdx)</Note>
+<Note>Contribute API gotchas by [editing this page](https://github.com/nangohq/nango/tree/master/docs-v2/integrations/all/jira-data-center.mdx)</Note>