Connect sanbase with discord

[tspenov]

Changes

Ticket

Checklist:

• I have performed a self-review of my own code
• I have made corresponding changes to the documentation
• I have tried to find clearer solution before commenting hard-to-understand parts of code
• I have added tests that prove my fix is effective or that my feature works

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Note

Introduce Discord verification codes generated on subscription, a /verify command that assigns PRO role, and supporting config, DB, admin, and tests.

• Discord Integration:
  • Context & API: Add Sanbase.Discord with discord_invite_url/0 and get_verification_info/1.
  • Verification Codes: New schema Sanbase.Discord.VerificationCode with generate/verify/retrieve/cleanup functions and configurable expiry.
• Billing Events:
  • On :create_subscription, generate Discord verification code for active paid plans; map plan to tier.
• Discord Bot:
  • Add /verify command handling: validate code, assign PRO role, send welcome message; helper methods for role/channel IDs and ephemeral interaction ack.
• Config:
  • New Sanbase.Discord settings: invite_url, verification_code_expiry_days.
• Database:
  • Migration creating discord_verification_codes table (+ indexes/FK); structure.sql updated.
• Admin:
  • Generic admin resource for DiscordVerificationCode (show-only, labels for Discord fields).
• Tests & Seeds:
  • Comprehensive tests for verification code lifecycle.
  • Test seed fallback to load products/plans from DB when ETS missing.

^{Written by Cursor Bugbot for commit 80e60ac. This will update automatically on new commits. Configure here.}

[tspenov]

@cursor review

[cursor]

Bug: Missing Plan Keys in Seeded Data

The seed_products_and_plans_from_db/0 fallback function returns an incomplete data structure. It includes only product keys, missing the various plan keys present in the original seeded data. This causes tests expecting those plan keys to fail or raise KeyError exceptions.