Automate Azure FinOps Workflows

My multi-subscription Azure estate is growing quickly and I need the core FinOps routines to move from manual spreadsheets to fully automated workflows right away. At the moment I rely almost exclusively on Azure Cost Management, but I am open to bringing in Advisor recommendations or Policy-based controls if they speed things up or add accuracy.

The automation must cover:
• Cost management: daily cost ingestion, tagging validation, alerting when spend drifts above threshold, and a weekly export to a Power BI workspace.
• Resource optimization: scheduled checks for idle or under-utilised resources with scripted actions (resize, shut down, or delete) that can be approved in-app or reverted if needed.
• Billing and invoicing: generation of monthly chargeback files per subscription, formatted for our finance system, plus email distribution to stakeholders.

Acceptance criteria
• Workflows run server-less or in a lightweight Azure DevOps/GitHub pipeline with clear ARM/Bicep or Terraform code so I can re-deploy in any region.
• All logic is parameterised and documented in a single README.
• A demo run proves each routine executes without manual touch.

I need an initial working version ASAP, ideally within the next week, with a short hand-over session so I can maintain it going forward.