performance: switch to object-based cursor from offset-based page cursors

[felickz]

Improve performance for large numbers of alerts - avoid potential 503 responses

• Also, page based endpoints are being shut down: https://github.blog/changelog/2025-09-23-upcoming-changes-to-github-dependabot-alerts-rest-api-offset-based-pagination-parameters-page-first-and-last/

Response header will now use object IDs:

Link: <https://api.github.com/organizations/###/secret-scanning/alerts?per_page=1&after=CAESBggBEgIIAioTCgwIwb6GxwYQwICyiQMQnZGNRP&secret_type=password>; rel="next"

Instead of page based:

Link: <https://api.github.com/organizations/###/secret-scanning/alerts?per_page=1&page=2>; rel="next", <https://api.github.com/organizations/###/secret-scanning/alerts?per_page=1&page=93323>; rel="last"

At least with dependabot, omitting the after empty param falls back to page number based cursor. Using that as a after= placeholder to force the behavior.

> gh api "/enterprises/ENT/dependabot/alerts" --include
HTTP/2.0 200 OK
...
Link: https://api.github.com/enterprises/ENT/dependabot/alerts?per_page=1&page=2; rel="next", https://api.github.com/enterprises/ENT/dependabot/alerts?per_page=1&page=104697; rel="last"

[Copilot]

Pull Request Overview

This PR switches GitHub API endpoints from offset-based pagination to cursor-based pagination for better performance when handling large numbers of alerts, avoiding potential 503 responses.

• Replaces page=1 query parameters with after= to force object-based cursor pagination
• Updates URL construction across secret scanning, Dependabot, and code scanning modules
• Maintains same functionality while improving API performance for large datasets

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 3 comments.

File	Description
src/secret_scanning.py	Updates API URLs to use cursor-based pagination for repository, organization, and enterprise secret scanning alerts
src/dependabot.py	Updates API URLs to use cursor-based pagination for Dependabot alerts across all scopes
src/code_scanning.py	Updates API URLs to use cursor-based pagination for code scanning alerts across all scopes

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[Copilot]

Pull Request Overview

Copilot reviewed 3 out of 3 changed files in this pull request and generated 2 comments.

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[Copilot]

The empty after= parameter may not be valid for GitHub's API. Consider either omitting the after parameter entirely for the first request or using a valid cursor value.

[Copilot]

The empty after= parameter may not be valid for GitHub's API. Consider either omitting the after parameter entirely for the first request or using a valid cursor value.