fix(ocsf): report the required device.os.type_id

[krishicks]

Summary

OCSF 1.8 requires type_id on the os object, but every OpenShell event reported device.os with only a name, so the events weren't schema-valid. Events now include device.os.type_id and its type label.

Related Issue

Refs #2912

This is one of several PRs that together satisfy #2912, so it does not close the issue.

Changes

• device.os reports Linux (200), Windows (100), or macOS (300). Any other platform reports Other (99), with the platform name as the type label.
• openshell-ocsf: a new OsTypeId enum, plus type_id, the type label, and OsInfo::for_target on OsInfo. Sandbox and gateway devices all build their OS info through for_target.
• The OCSF 1.8.0 os object schema is now vendored, so tests validate device.os. It was missing before, which is why the omission wasn't caught.
• Docs: ocsf-json-export.mdx describes device.os.type_id and updates the example record.

Before:

"os": { "name": "Linux" }

After:

"os": { "name": "Linux", "type_id": 200, "type": "Linux" }

Testing

• cargo nextest run -p openshell-ocsf -p openshell-otel -p openshell-server (2600 passed)
• cargo clippy --workspace --all-targets -- -D warnings
• Unit tests added: OS type mapping per platform, and validation of every device's os against the vendored schema
• E2E tests added/updated (not applicable)

Checklist

• Follows Conventional Commits
• Commits are signed off (DCO)

[github-actions]

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