Fix GitHub repository URL in CI workflows

Update placeholder repository URLs from 'yourusername' to the actual
repository owner 'ChristosDev75' in the workflow files.

This fixes the CI failure when attempting to install c4-literate-python
during the validation step.

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

Author: christosm-dev

.github/workflows/notes-api-ci-validation-only.yml

@@ -49,7 +49,7 @@ jobs:
         # For now, install from local path or git repo
         # Replace with: pip install c4-literate-python
         # once published to PyPI
-        pip install git+https://github.com/yourusername/c4-literate-python.git@main
+        pip install git+https://github.com/ChristosDev75/c4-literate-python.git@main
     
     - name: Validate C4 annotations
       run: |

.github/workflows/notes-api-ci-workflow.yml

@@ -50,7 +50,7 @@ jobs:
     - name: Install c4-literate-python
       run: |
         # Clone the c4-literate-python tool
-        git clone https://github.com/yourusername/c4-literate-python.git
+        git clone https://github.com/ChristosDev75/c4-literate-python.git
         cd c4-literate-python
         pip install -e .