Overhaul Free Plan with Stripe-Based 'X'-Day Trial System and Subscription Flow Enhancements

[Ashad001]

This pull request replaces the previous free plan with a robust X-day (to be changed later) trial system backed by Stripe's manual payment capture. The goal is to create a more controlled and secure subscription flow, simplify credit handling, and fully automate the transition between trial, active, and canceled states using Stripe webhooks and Redis.

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What This PR Achieves:

• Removes the free plan and replaces it with a x-day trial that requires a valid payment method up front.
• Implements Stripe’s manual capture system to charge users only after the trial ends.
• Automates credit allocation and reset logic based on user actions (signup, trial end, cancellation).
• Strengthens backend reliability by shifting all billing logic to Stripe webhooks and ensuring Redis stays the single source of truth.
• Aligns frontend UI and state with the new subscription logic, including trial indicators, credit status, and cancellation behavior.
• Improves maintainability with better environment configuration, security upgrades, and documentation.

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Key Changes:

Frontend:

• Enhanced /account page to:

  • Reflect trial and subscription states.
  • Trigger credit updates via events.
  • Handle trial-based cancellations properly.

• Credit UI updated to reflect new billing logic (no more free plan credits).

Configuration + Codebase Hygiene:

• .env-template: Added NODE_ENV, updated ADMIN_API_KEY.
• .gitignore: Excluded scripts/ for cleanliness.

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Outcome:

This update strengthens the revenue model, improves billing transparency, prevents abuse of the free tier, and sets the foundation for a scalable, automated trial-to-paid flow.