Create Input Package: Windows Event Log receiver

Develop an input package for the Windows Event Log receiver that's installable + configurable via Fleet and can be deployed to Hybrid Agent.

## Receiver Documentation

https://github.com/open-telemetry/opentelemetry-collector-contrib/tree/main/receiver/windowseventlogreceiver

## Definition of Done

- [ ] Published to epr.elastic.co as tech preview
- [ ] Installs via Kibana UI and Fleet API
- [ ] Deploys to Agent + starts collector running receiver
- [ ] Ingests sample data to `otel.windows event log-*` datastream
- [ ] Mapping matches OTel-native format ([spec](https://docs.elastic.dev/ingest-dev-docs/otel/data-model#otel-native-storage-format-semanticconventions-aligned))
- [ ] Content pack auto-installs (if exists)
- [ ] `elastic-package test` passes
- [ ] Manual smoke test documented in PR
- [ ] README includes purpose, sample config, troubleshooting steps, relevant links
- [ ] GitHub Codeowner is `@elastic/ecosystem`
- [ ] Optional review from team owning ECS equivalent
- [ ] Table in parent issue is updated with PR link and anything else of note