[Github] Add storage name option to entity attributes

[shopwareBot]

1. Why is this change necessary?

As discussed in Slack, there is a need for some consistency with the previous way of creating definitions where you can influence the storagename.

2. What does this change do, exactly?

Add the option to change the storage name for fields defined with entity attributes.

4. Please link to the relevant issues (if any).

https://shopwarecommunity.slack.com/archives/C011VFQT7GB/p1718088460270309

5. Checklist

• [ ] I have rebased my changes to remove merge conflicts
• [x] I have written tests and verified that they fail without my change
• [x] I have created a changelog file with all necessary information about my changes
• [ ] I have written or adjusted the documentation according to my changes
• [x] This change has comments for package types, values, functions, and non-obvious lines of code
• [ ] I have read the contribution requirements and fulfil them.

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Imported from Github. Please see: https://github.com/shopware/shopware/pull/3766

[shopware-issue-bot[bot]]

We found the following existing issues which may help or are related to your topic:

• [Github] Add storage name option to entity attributes
• Add storage name option to entity attributes
• [github] Fix custom entity repository definitions
• [github] Custom fields in category entity
• Fix custom entity repository definitions
• [github] Bugfix autowiring type+name for already defined repositories
• Entity definition via attributes generates errors
• [Github] Add title attribute to sw_cms_list_item
• [GitHub] needed for custom field integration / data mapping
• "Missing translated storage aware property" with user defined searchable content

[shopwareBot]

[public] Automated response: This issue is linked to the internal issue https://shopware.atlassian.net/browse/NEXT-36782.

[created from NEXT-36782, comment 484687]