Replace term "storage apps" with "projects"

[maureensturgeon]

The table pegasus.storage_apps has been migrated to dashboard.projects (#45480), however there are still many references to the term "storage apps".

In this PR

• an alias is created for the active record models ChannelTokens and Backpacks to rename storage_app_id to project_id
• the class StorageApps has been renamed to Projects and all references have been updated

Links

• jira ticket: LP-2272

Testing story

Tested some project scenarios locally

PR Checklist:

• Tests provide adequate coverage
• Privacy and Security impacts have been assessed
• Code is well-commented
• New features are translatable or updates will not break translations
• Relevant documentation has been added or updated
• User impact is well-understood and desirable
• Pull Request is labeled appropriately
• Follow-up work items (including potential tech debt) are tracked and linked