[FIX] Remove out in favor of rlog

[bbengfort]

Scope of changes

There is no reason to have the out package now that we have the rlog package. Also, it wasn't being used, so better to clean it up.

Type of change

• new feature
• bug fix
• documentation
• testing
• technical debt
• other (describe)

Author checklist

• I have manually tested the change and/or added automation in the form of unit tests or integration tests
• I have added new test fixtures as needed to support added tests

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Note

Medium Risk
This is a breaking change for any downstream consumers importing go.rtnl.ai/x/out, though the repo itself no longer references it. No runtime logic is modified outside of deleting the package.

Overview
Removes the out hierarchical stdout logger subpackage entirely (source, tests, and its README), effectively deprecating the go.rtnl.ai/x/out import path.

Updates the root README.md subpackage list to drop the out entry and point consumers toward rlog instead.

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