⚡ (billing) Automatic usage-based billing (#924)

BREAKING CHANGE: Stripe environment variables simplified. Check out the
new configs to adapt your existing system.

Closes #906





<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
### Summary by CodeRabbit

**New Features:**
- Introduced a usage-based billing system, providing more flexibility
and options for users.
- Integrated with Stripe for a smoother and more secure payment process.
- Enhanced the user interface with improvements to the billing,
workspace, and pricing pages for a more intuitive experience.

**Improvements:**
- Simplified the billing logic, removing additional chats and yearly
billing for a more streamlined user experience.
- Updated email notifications to keep users informed about their usage
and limits.
- Improved pricing and currency formatting for better clarity and
understanding.

**Testing:**
- Updated tests and specifications to ensure the reliability of new
features and improvements.

**Note:** These changes aim to provide a more flexible and user-friendly
billing system, with clearer pricing and improved notifications. Users
should find the new system more intuitive and easier to navigate.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->

packages/scripts/inspectUser.ts

@@ -39,7 +39,6 @@ const inspectUser = async () => {
                   user: { email: { not: response.email } },
                 },
               },
-              additionalChatsIndex: true,
               additionalStorageIndex: true,
               typebots: {
                 orderBy: {
@@ -82,10 +81,6 @@ const inspectUser = async () => {
     console.log('  - Name:', workspace.workspace.name)
     console.log('    Plan:', workspace.workspace.plan)
     console.log('    Members:', workspace.workspace.members.length + 1)
-    console.log(
-      '    Additional chats:',
-      workspace.workspace.additionalChatsIndex
-    )
     console.log(
       '    Additional storage:',
       workspace.workspace.additionalStorageIndex