Create missing adr/ and standards/ directories referenced in README

[jeanmachuca]

What

The README lists adr/ and standards/ directories but they don't exist in the repository.

Why

• Readers of the README will expect these directories to exist
• ADRs (Architecture Decision Records) are critical for documenting technical decisions over time
• Coding standards help maintain consistency across the project's 6 Go repos

How

Either:

• Create the adr/ and standards/ directories with placeholder index files
• Or remove the references from README if these directories are not planned

Recommended

• adr/0001-record-architecture-decisions.md (template)
• standards/README.md (placeholder)