feat: add Pa11y accessibility testing + migrate GitHub refs to Gitea

- Add Pa11y CI config template (templates/configs/pa11yci.json)
- Replace all github.com/mokoconsulting-tech with git.mokoconsulting.tech/MokoConsulting
- Update .moko-standards governance file

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

CONTRIBUTING.md

@@ -8,7 +8,7 @@
  # FILE INFORMATION
  DEFGROUP: Joomla.Template
  INGROUP: MokoCassiopeia.Governance
- REPO: https://github.com/mokoconsulting-tech/MokoCassiopeia
+ REPO: https://git.mokoconsulting.tech/MokoConsulting/MokoCassiopeia
  FILE: CONTRIBUTING.md
  VERSION: 03.09.03
  BRIEF: Contribution guidelines for the MokoCassiopeia project.
@@ -43,7 +43,7 @@ For first-time contributors:
 
 ```bash
 # Clone the repository
-git clone https://github.com/mokoconsulting-tech/MokoCassiopeia.git
+git clone https://git.mokoconsulting.tech/MokoConsulting/MokoCassiopeia.git
 cd MokoCassiopeia
 ```
 
@@ -130,7 +130,7 @@ Participation in this project is governed by the Code of Conduct. Unacceptable b
 ## Metadata
 
 * **Document:** CONTRIBUTING.md
-* **Repository:** [https://github.com/mokoconsulting-tech/MokoCassiopeia](https://github.com/mokoconsulting-tech/MokoCassiopeia)
+* **Repository:** [https://git.mokoconsulting.tech/MokoConsulting/MokoCassiopeia](https://git.mokoconsulting.tech/MokoConsulting/MokoCassiopeia)
 * **Path:** /CONTRIBUTING.md
 * **Owner:** Moko Consulting
 * **Version:** 03.06.00