Fix broken GitLab CI pipelines after enabling DrupalCI templates

Problem/Motivation

The first GitLab CI pipeline after enabling .gitlab-ci.yml (pipeline #856060, commit 94b9ac94) failed.

The phpunit job cannot install the module’s dependencies because the repository has no composer.json. All kernel and functional tests fail with errors such as:

• Unavailable module: 'mcp_server'. If this module needs to be downloaded for testing, include it in the 'require-dev' section of your composer.json file.
• Unavailable module: 'tool'. (required transitively by mcp_server and listed in ContentTypeListResourceTest::$modules)

Additionally, the cspell job (allowed to fail, but still red) reports unrecognized words, including project-specific terms like kenkeep, groundstrokes, baseliner, handers, and base64-encoded image data embedded in prompt config YAML files.

Proposed resolution

1. Add a composer.json that declares the module’s runtime and test dependencies, at minimum:
   • drupal/mcp_server: ^2.0

   This will pull in transitive dependencies such as drupal/tool so the PHPUnit job can enable the required modules.

2. Fix the cspell failures by:
   • Adding legitimate project words to the project dictionary or cspell configuration (e.g. kenkeep, groundstrokes, baseliner, handers).
   • Configuring cspell to ignore base64-encoded image strings in config/install/*.yml files.

Remaining tasks

• [ ] Add composer.json with required dependencies.
• [ ] Confirm PHPUnit job can install and enable mcp_server and tool.
• [ ] Configure cspell to ignore base64 image data and add project-specific words.
• [ ] Confirm the full pipeline is green on 1.x.

User interface changes

None.

API changes

None.

Data model changes

None.

Testing instructions

1. Push a branch with the proposed changes.
2. Open a merge request and wait for the GitLab CI pipeline.
3. Verify the pipeline at https://git.drupalcode.org/project/mcp_server_examples/-/pipelines is green.
4. Confirm the phpunit and cspell jobs pass.