Implement agent logging preamble spec

[z1c0]

Description

See:

• https://github.com/elastic/apm/pull/713
• https://github.com/elastic/apm/blob/main/specs/agents/logging.md#logging-preamble

Agent Issues

• [x] https://github.com/elastic/apm-agent-java/issues/2905
• [x] https://github.com/elastic/apm-agent-dotnet/issues/1937
• [ ] https://github.com/elastic/apm-agent-nodejs/issues/3060
• [ ] https://github.com/elastic/apm-agent-python/issues/1706
• [ ] https://github.com/elastic/apm-agent-go/issues/1361
• [ ] https://github.com/elastic/apm-agent-php/issues/832
• [ ] https://github.com/elastic/apm-agent-ruby/issues/1327