Warn when a pre-deploy directory upload will not be reused

## Problem

`abx storage upload ` followed by a normal directory deployment does not reuse the prior upload; the deploy command uploads the directory again. This is confusing on IPFS and can duplicate paid permanent storage on Arweave.

## Desired outcome

Make the non-reuse behavior explicit and provide a supported reuse workflow if one is intended.

## Acceptance criteria

- Warn before or after directory upload that deploy commands will upload their source independently.
- Point users to a supported locator-based workflow when reuse is possible; otherwise state that it is not supported.
- Do not warn for single-file upload intended for `abx attach`.
- Add CLI/help tests and update the storage guide.

Start from the CLI entry points for storage upload and directory deployment, then read the storage guide and existing CLI/help tests mentioned in the issue. Trace how directory and single-file uploads are distinguished and identify the supported locator-based reuse path, if any. Done means the warning and guidance appear only for directory uploads, tests cover the behavior, and the storage guide is updated.

Written by the indexing model from the issue text.