EPIC: OVHcloud plugin (plugin-ovhcloud)

## Summary

This EPIC tracks the creation of `plugin-ovhcloud`, a comprehensive OSS Kestra plugin integrating the full OVHcloud product catalog — from compute and storage to AI workloads, networking, domain management, and observability. The plugin will enable data and platform engineering teams to orchestrate their entire OVHcloud infrastructure directly from Kestra flows, using a single `io.kestra.plugin.ovhcloud` namespace.

## Plugins in Scope

- **Compute** — Manage Public Cloud instances (Nova), bare metal dedicated servers, and Managed Kubernetes (OVH MKS) clusters and node pools.
- **Storage** — Orchestrate S3-compatible Object Storage, Cold Archive (tape), Block Storage volumes, and Managed Databases (PostgreSQL, MySQL, MongoDB, Redis, Kafka, OpenSearch, etc.).
- **Networking** — Automate Load Balancers (ipLoadbalancing), vRack private networks, Floating IPs, and DNS zones.
- **AI & ML** — Submit and monitor AI Training jobs, deploy and scale AI Deploy apps, and manage AI Notebooks.
- **Domains & Web** — Manage domain registrations, DNS zone records, nameservers, and SSL/TLS certificates.
- **Monitoring / Logs** — Configure Logs Data Platform (LDP) inputs, streams, and OpenSearch indexes; manage Metrics (Warp10/OpenTSDB/Prometheus) tokens and quotas.

## Repository

- **Repository**: `plugin-ovhcloud`
- **Namespace**: `io.kestra.plugin.ovhcloud`
- **Type**: OSS (public repository)
- **Authentication**: OVHcloud 3-key HMAC (Application Key + Application Secret + Consumer Key) for all management-plane calls; AWS Signature V4 for S3-compatible storage; OAuth2 service-account bearer token for CI/CD and short-lived credentials.

## Sub-issues

## Acceptance Criteria

- [ ] All sub-issues listed above are implemented, reviewed, and merged
- [ ] Shared `OvhConnection` abstract base class handling both HMAC and OAuth2 auth is implemented once and reused across sub-plugins
- [ ] Each sub-plugin domain has its own `package-info.java` with `@PluginSubGroup`
- [ ] `metadata/index.yaml` and plugin icon SVG present in the root repository
- [ ] All tasks and triggers support Kestra expression language (`Property` fields)
- [ ] Integration documented in the Kestra docs

Start by reviewing the acceptance criteria and the planned sub-plugin domains in the plugin-ovhcloud repository; no sub-issues are linked yet. Work would need to cover OvhConnection, each domain's package-info.java, metadata/index.yaml, the plugin icon SVG, expression support, and documentation, with all acceptance criteria completed.

Written by the indexing model from the issue text.