feat: add pagination support when fetching repository environments

[Sylfwood]

Fixes #278

Fetching environments was limited to 30 environments. This change use pagination to support fetching all environments.

Example:

A repository with 35 environments:

Before

Only 30 environments were fetched by the extension.

After

All 35 environments are correctly fetched.

[Copilot]

Pull Request Overview

Adds support for fetching more than the default 30 repository environments by requesting up to 100 per page.

• Introduces a per_page: 100 parameter to the GitHub API call.
• Ensures environments beyond the default 30 are included in the returned result.

Comments suppressed due to low confidence (1)

src/treeViews/settings/environmentsNode.ts:12

• Add tests for the pagination logic to ensure repositories with more than 100 environments are fully fetched.

async getEnvironments(): Promise<EnvironmentNode[]> {

[Copilot]

Pull Request Overview

This PR adds pagination support when fetching repository environments from GitHub so that all environments are correctly fetched instead of being limited to 30.

• Uses the GitHub API endpoint merge to configure request parameters.
• Leverages the paginate API to retrieve all environments across pages.