docs: update Prisma version refs to 7.5.0-dev.33, add partial index docs

- Update SETUP.md, ARCHITECTURE.md version references
- Document 8 partial indexes in wiki/Database-Schema.md
- Add Prisma 7.3+ schema features table to wiki/Architecture.md

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: ABCrimson

ARCHITECTURE.md

@@ -112,7 +112,7 @@ Shared Prisma 7 database package.
 
 **Tables:** users, accounts, sessions, worksheets, folders, forum_posts, comments, upvotes, audit_logs
 
-**Tech:** Prisma 7.5.0-dev.32, @neondatabase/serverless 1.0.2, @prisma/adapter-neon
+**Tech:** Prisma 7.5.0-dev.33, @neondatabase/serverless 1.0.2, @prisma/adapter-neon
 
 ### @nextcalc/api
 

docs/SETUP.md

@@ -185,7 +185,7 @@ Create **separate** OAuth apps for production:
 | Next.js | 16.2.0-canary.69 |
 | React | 19.3.0-canary |
 | TypeScript | 6.0.0-dev.20260301 |
-| Prisma | 7.5.0-dev.32 |
+| Prisma | 7.5.0-dev.33 |
 | Apollo Server | 5.4.0 |
 | Biome | 2.5.0 |
 | Turborepo | 2.8.13-canary.8 |

docs/wiki/Architecture.md

@@ -116,9 +116,9 @@ WebSocket subscriptions authenticate via JWT tokens passed in the connection `co
 
 The Cloudflare rate-limiter Worker uses timing-safe comparison (`crypto.subtle.timingSafeEqual`) for API key validation, preventing timing-based side-channel attacks on the shared secret.
 
-## Prisma 7 Adapter Pattern
+## Prisma 7.5 Adapter Pattern
 
-The database package uses Prisma 7's Neon serverless adapter. The adapter constructor takes a **config object**, not a Pool instance:
+The database package uses Prisma 7.5.0-dev.33's Neon serverless adapter. The adapter constructor takes a **config object**, not a Pool instance:
 
 ```typescript
 // Correct
@@ -131,6 +131,15 @@ const adapter = new PrismaNeon(pool);
 
 Prisma 7 creates its own connection pool internally via the adapter's `connect()` method.
 
+### Schema Features (7.3+)
+
+| Feature | Since | Description |
+|:--------|:------|:------------|
+| `compilerBuild = "fast"` | 7.3 | Speed-optimized query compiler (larger footprint, ideal for Node.js) |
+| `partialIndexes` preview | 7.4 | Filtered indexes with `WHERE` conditions for smaller, faster lookups |
+| Query plan caching | 7.4 | LRU cache for compiled query plans (~100% hit rate for repeated shapes) |
+| BigInt precision in JSON | 7.3 | BigInt values cast to text inside JSON aggregation with `relationJoins` |
+
 ## Styling System
 
 - **OKLCH** color tokens in `apps/web/app/globals.css`

docs/wiki/Database-Schema.md

@@ -1,6 +1,6 @@
 # Database Schema
 
-Prisma 7 with Neon PostgreSQL serverless adapter. Schema: `packages/database/prisma/schema.prisma`.
+Prisma 7.5.0-dev.33 with Neon PostgreSQL serverless adapter. Schema: `packages/database/prisma/schema.prisma`.
 
 ---
 
@@ -136,3 +136,20 @@ Key indexes for query performance:
 | `postId` | Comment | List comments on a post |
 | `parentId` | Folder, Comment | Traverse nested hierarchies |
 | `shortCode` | SharedCalculation | Unique lookup for shared links |
+
+### Partial Indexes (Prisma 7.4+)
+
+Filtered indexes that only include non-deleted records. PostgreSQL automatically prefers these smaller indexes when queries include `WHERE deletedAt IS NULL`, dramatically reducing I/O for the vast majority of reads.
+
+| Index Name | Model | Columns | Filter |
+|:-----------|:------|:--------|:-------|
+| `worksheets_userId_visibility_active_idx` | Worksheet | userId, visibility | `deletedAt IS NULL` |
+| `worksheets_createdAt_active_idx` | Worksheet | createdAt DESC | `deletedAt IS NULL` |
+| `forum_posts_createdAt_active_idx` | ForumPost | createdAt DESC | `deletedAt IS NULL` |
+| `forum_posts_isPinned_createdAt_active_idx` | ForumPost | isPinned, createdAt DESC | `deletedAt IS NULL` |
+| `comments_postId_active_idx` | Comment | postId | `deletedAt IS NULL` |
+| `comments_parentId_active_idx` | Comment | parentId | `deletedAt IS NULL` |
+| `problems_difficulty_popularity_active_idx` | Problem | difficulty, popularity DESC | `deletedAt IS NULL` |
+| `problems_createdAt_active_idx` | Problem | createdAt DESC | `deletedAt IS NULL` |
+
+Defined in schema using Prisma 7.4's type-safe syntax: `@@index([field], map: "name", where: { deletedAt: null })`