feat: add changelog fragments workflow (#11886)

Co-authored-by: Adrián Peña <adrianjpr@gmail.com>

docs/developer-guide/provider.mdx

@@ -3421,7 +3421,7 @@ Use existing providers as templates, this will help you to understand better the
 - **Documentation & Maintenance**
 
     - **README Updates**: Update provider-specific documentation
-    - **Changelog**: Document changes and new features
+    - **Changelog**: Document changes and new features with a fragment under `prowler/changelog.d/` (see the [Pull Request Template](https://github.com/prowler-cloud/prowler/blob/master/.github/pull_request_template.md))
     - **Examples**: Provide usage examples and common scenarios
     - **Troubleshooting**: Include common issues and solutions
     - **Documentation**: Update the provider documentation to include your new tool provider in the examples and implementation guidance.

docs/developer-guide/security-compliance-framework.mdx

@@ -778,7 +778,7 @@ Before opening the pull request:
     uv run pre-commit run --all-files
     uv run pytest -n auto
     ```
-2. Add a changelog entry under the `### 🚀 Added` section of `prowler/CHANGELOG.md`, describing the new framework and the providers it covers.
+2. Add a changelog fragment `prowler/changelog.d/<slug>.added.md`, describing the new framework and the providers it covers (no PR link in the text; it is attached automatically at release time).
 3. Follow the [Pull Request Template](https://github.com/prowler-cloud/prowler/blob/master/.github/pull_request_template.md) and set the PR title using Conventional Commits, e.g. `feat(compliance): add My Framework 1.0 for AWS`.
 4. Request review from the compliance codeowners listed in `.github/CODEOWNERS`.