⚡ (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 -->

.github/workflows/check-and-report-chats-usage.yml

@@ -1,4 +1,4 @@
-name: Send chats limit alert emails
+name: Check and report chats usage
 
 on:
   schedule:
@@ -22,8 +22,9 @@ jobs:
       SMTP_HOST: '${{ secrets.SMTP_HOST }}'
       SMTP_PORT: '${{ secrets.SMTP_PORT }}'
       NEXT_PUBLIC_SMTP_FROM: '${{ secrets.NEXT_PUBLIC_SMTP_FROM }}'
+      STRIPE_SECRET_KEY: '${{ secrets.STRIPE_SECRET_KEY }}'
     steps:
       - uses: actions/checkout@v2
       - uses: pnpm/action-setup@v2.2.2
       - run: pnpm i --frozen-lockfile
-      - run: pnpm turbo run sendAlertEmails
+      - run: pnpm turbo run checkAndReportChatsUsage

.github/workflows/send-total-results-digest.yml

@@ -1,24 +0,0 @@
-name: Send total results daily digest
-
-on:
-  schedule:
-    - cron: '0 5 * * *'
-
-jobs:
-  send:
-    runs-on: ubuntu-latest
-    defaults:
-      run:
-        working-directory: ./packages/scripts
-    env:
-      DATABASE_URL: '${{ secrets.DATABASE_URL }}'
-      ENCRYPTION_SECRET: '${{ secrets.ENCRYPTION_SECRET }}'
-      NEXTAUTH_URL: 'http://localhost:3000'
-      NEXT_PUBLIC_VIEWER_URL: 'http://localhost:3001'
-      TELEMETRY_WEBHOOK_URL: '${{ secrets.TELEMETRY_WEBHOOK_URL }}'
-      TELEMETRY_WEBHOOK_BEARER_TOKEN: '${{ secrets.TELEMETRY_WEBHOOK_BEARER_TOKEN }}'
-    steps:
-      - uses: actions/checkout@v2
-      - uses: pnpm/action-setup@v2.2.2
-      - run: pnpm i --frozen-lockfile
-      - run: pnpm turbo run telemetry:sendTotalResultsDigest