fix: quality-adjusted SM-2 first intervals and review UX freeze

[prithaxdev]

• sm2.py: first review now gives 4-day interval for Easy (quality>=4) and 2-day for Hard (quality==3) instead of always 1; Forgot unchanged
• test_sm2.py: replace fixed-interval test with separate Easy/Hard cases
• use-review.ts: fix query key mismatch — invalidate snippetKeys.due with clerkId to match useDueSnippets, not Supabase UUID; keep supabaseUserId for review log invalidation
• review-session.tsx: track submittingRating (1|3|5|null) per click; wrap mutateAsync in try/catch so errors show an inline banner instead of silently freezing
• review-card.tsx: spinner replaces label on the active rating button while request is in-flight; idle buttons dim to 40% (not 50%)

Summary by CodeRabbit

Release Notes

• New Features

  • Quality-based scheduling for initial reviews: high-confidence ratings now schedule 4 days ahead, while moderate-confidence ratings schedule 2 days ahead.

• Improvements

  • Enhanced review interface with visual feedback indicating which rating is being submitted, including a loading animation.
  • Added error handling and user-facing messages for failed review submissions.

[coderabbitai]

Caution

Review failed

The pull request is closed.

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Free

Run ID: 6d625fe2-7543-40d9-b5c5-3546eaa44335

📥 Commits

Reviewing files that changed from the base of the PR and between 6349c5b and e9675ec.

📒 Files selected for processing (5)

• apps/api/app/algorithms/sm2.py
• apps/api/tests/test_sm2.py
• apps/web/components/review-card.tsx
• apps/web/components/review-session.tsx
• apps/web/hooks/use-review.ts

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📝 Walkthrough

Walkthrough

Changes update the SM-2 spaced repetition algorithm to use quality-based scheduling on first-memory success, update corresponding tests, and enhance the review card UI to display which rating is being submitted with improved error handling in the submission flow.

Changes

Cohort / File(s)	Summary
SM-2 Algorithm and Tests apps/api/app/algorithms/sm2.py, apps/api/tests/test_sm2.py	Updated SM-2 first-success scheduling to use quality-conditioned intervals: quality ≥ 4 schedules 4 days, quality [3, 4) schedules 2 days (previously fixed to 1 day). Tests updated to assert new interval expectations for Easy and Hard quality ratings on first review.
Review Card UI Enhancements apps/web/components/review-card.tsx, apps/web/components/review-session.tsx	Replaced boolean isSubmitting with submittingRating to track which specific rating is being processed. Active rating button shows spinning loader and "Saving…" text; inactive ratings show normal text with reduced opacity. Added error handling to display error banner when submission fails, with state reset on completion.
Review Hook Authentication apps/web/hooks/use-review.ts	Changed query invalidation to use Clerk's clerkId for due-snippet queries instead of Supabase user id; added separate Supabase id retrieval with conditional invalidation to prevent calls with undefined identifiers.

Sequence Diagram

sequenceDiagram
    participant User
    participant ReviewSession
    participant ReviewCard
    participant API as API/Mutation

    User->>ReviewSession: Click rating button
    activate ReviewSession
    ReviewSession->>ReviewSession: Set submittingRating state
    ReviewSession->>ReviewCard: Pass submittingRating prop
    activate ReviewCard
    ReviewCard->>ReviewCard: Render loader for active rating<br/>Show "Saving…" text
    ReviewCard-->>ReviewSession: (visual feedback)
    deactivate ReviewCard
    ReviewSession->>API: mutateAsync (submit review)
    activate API
    alt Success
        API-->>ReviewSession: Success response
        ReviewSession->>ReviewSession: Advance session index/done
    else Failure
        API-->>ReviewSession: Error response
        ReviewSession->>ReviewSession: Store submitError message
        ReviewSession->>ReviewCard: Error banner renders
    end
    ReviewSession->>ReviewSession: Reset submittingRating (finally)
    deactivate API
    deactivate ReviewSession

Loading

Estimated code review effort

🎯 3 (Moderate) | ⏱️ ~25 minutes

Poem

🐰 The spacing grows with wisdom's might,
First memories now pace just right—
Two days or four, by quality's call,
While rating buttons dance through all,
With loaders spinning, errors caught,
A smoother flow our review has wrought!

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