feat: IaC maturity tracking automation and scoring dashboard

[kristopherjturner]

Overview

Automate the IaC maturity tracking and scoring system so that each solution repo's infrastructure code completeness is measured, scored, and reported automatically — replacing manual tracking.

Scope

• Maturity model definition: scoring rubric for each maturity dimension (config completeness, test coverage, CI/CD, documentation, schema validation)
• tools/maturity-score.ps1 — script that scores a target repo against the maturity rubric
• GitHub Actions workflow: run maturity scoring on each solution repo weekly and post results
• Maturity dashboard: GitHub repository README badge + central dashboard in toolkit docs
• Threshold alerting: notify via GitHub issue if a repo's score drops below threshold

Acceptance Criteria

• Maturity rubric defined with clear scoring criteria per dimension
• Scoring script runs against any solution repo from its checkout path
• Weekly scheduling via GitHub Actions, results posted as repo issue comment
• Dashboard shows current maturity score for all 5 solution repos
• Score badges generated for each repo's README

Dependencies

• Parent Epic: [Epic] Azure Local Toolkit Platform Automation Full Build-Out #9
• Variable registry: feat: variable registry implementation (shared config for all solution repos) #10
• Existing maturity tracking issue: Track IaC tool maturity status across all repos (Built / Tested / Released) #5

[kristopherjturner]

Related to #16 (TKT-6) — Research: Azure Deployment Stacks for ARM/Bicep Deployments. Implementation of this issue should account for deployment stack adoption across all repos.