feat: standards replication mechanism across all solution repos

[kristopherjturner]

Overview

Build the standards replication mechanism that propagates shared conventions — naming policies, tagging standards, pipeline templates, and configuration schemas — from the toolkit to all solution repos consistently and automatically.

Scope

• GitHub Actions workflow template library (pipelines/templates/) for reuse across solution repos
• tools/replicate-standards.ps1 — script that pushes updated templates/configs to all downstream repos (via PR)
• Naming convention schema (resource names, file naming, branch naming)
• Tagging policy definitions (required tags, allowed values)
• Changelog: track what standards version each solution repo is on
• Notification: PR raised in each affected repo when standards update

Acceptance Criteria

• Standards replication tool creates PRs in all downstream repos when templates change
• Naming convention and tagging schemas are documented and enforced via policy
• All solution repos pinned to a toolkit standards version
• Standard pipeline templates deployed to ≥3 solution repos

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 standards mechanism issue: Create standards replication mechanism from docs site to all repos #6