Publish form count KPI metrics to CloudWatch

[theseanything]

What problem does this pull request solve?

Trello card: https://trello.com/c/b3cNvzu5/3136-record-kpis-in-cloudwatch

This adds automated form count metrics to CloudWatch so we can track how the platform is growing over time and measure the impact of our work. A new service publishes counts grouped by organisation and state (live, archived, draft), and a metrics:export_form_counts rake task will run on a scheduled cron job to publish those metrics on a regular basis. This lays the foundation for KPI reporting without manual updates.

[Copilot]

Pull request overview

This PR introduces automated KPI publishing for form counts to AWS CloudWatch, enabling ongoing platform growth tracking without manual reporting.

Changes:

• Added Metrics::FormCountService to aggregate form counts by organisation and form state and publish them to CloudWatch.
• Added a metrics:export_form_counts rake task intended for scheduled execution.
• Added specs covering the service publishing behaviour and the rake task wiring.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 1 comment.

File	Description
app/services/metrics/form_count_service.rb	Implements aggregation + CloudWatch publishing for per-org/per-state form counts.
lib/tasks/metrics.rake	Adds scheduled-entry rake task to trigger publishing.
spec/services/metrics/form_count_service_spec.rb	Verifies CloudWatch payload structure and error capture/re-raise behaviour.
spec/lib/tasks/metrics.rake_spec.rb	Ensures rake task invokes Metrics::FormCountService#publish_form_counts.

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[Copilot]

Pull request overview

Copilot reviewed 6 out of 7 changed files in this pull request and generated 3 comments.

[github-actions]

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