docs: migrate web storage implementation from wa-sql to absurd-sql

- Update web platform storage solution to use absurd-sql with IndexedDB backend

- Replace wa-sqlite dependencies with absurd-sql and @jlongster/sql.js

- Update WebSQLiteService implementation with SQLiteFS and IndexedDBBackend

- Add performance optimizations (WAL mode, mmap, temp store)

- Add type-safe query method and improved error handling

- Update platform capabilities matrix with new features

- Add absurd-sql compatibility checks in migration service

This change improves transaction support, performance, and reliability of the web platform's SQLite implementation.

doc/secure-storage-implementation.md

@@ -5,7 +5,7 @@
 This document outlines the implementation of secure storage for the TimeSafari app using Capacitor solutions. The implementation focuses on:
 
 1. **Platform-Specific Storage Solutions**:
-   - Web: wa-sqlite with IndexedDB backend
+   - Web: absurd-sql with IndexedDB backend
    - iOS: SQLCipher with Keychain integration
    - Android: SQLCipher with Keystore integration
    - Electron: SQLite with secure storage
@@ -23,8 +23,8 @@ This document outlines the implementation of secure storage for the TimeSafari a
 ```bash
 # Core dependencies
 npm install @capacitor-community/sqlite@6.0.0
-npm install @wa-sqlite/sql.js@0.8.12
-npm install @wa-sqlite/sql.js-httpvfs@0.8.12
+npm install absurd-sql@latest
+npm install @jlongster/sql.js@latest
 
 # Platform-specific dependencies
 npm install @capacitor/preferences@6.0.2
@@ -218,13 +218,18 @@ try {
 
 ### 4. Platform-Specific Implementations
 
-#### Web Platform (wa-sqlite)
+#### Web Platform (absurd-sql)
 
 ```typescript
 // src/services/platforms/web/WebSQLiteService.ts
+import { initSqlJs } from '@jlongster/sql.js';
+import { SQLiteFS } from 'absurd-sql';
+import IndexedDBBackend from 'absurd-sql/dist/indexeddb-backend';
+import { StorageError, StorageErrorCodes } from '../errors/StorageError';
+
 export class WebSQLiteService implements PlatformService {
   private db: SQLite.Database | null = null;
-  private vfs: IDBBatchAtomicVFS | null = null;
+  private vfs: SQLiteFS | null = null;
   private initialized = false;
 
   async initialize(): Promise<void> {
@@ -258,8 +263,8 @@ export class WebSQLiteService implements PlatformService {
 
   private async initializeSQLite(): Promise<SQLite.SqlJsStatic> {
     try {
-      return await SQLite.init({
-        locateFile: file => `https://cdn.jsdelivr.net/npm/@wa-sqlite/sql.js@0.8.12/dist/${file}`
+      return await initSqlJs({
+        locateFile: file => `https://cdn.jsdelivr.net/npm/@jlongster/sql.js@latest/dist/${file}`
       });
     } catch (error) {
       throw new StorageError(
@@ -272,8 +277,14 @@ export class WebSQLiteService implements PlatformService {
 
   private async setupVFS(sqlite3: SQLite.SqlJsStatic): Promise<void> {
     try {
-      this.vfs = new IDBBatchAtomicVFS('timesafari');
-      await this.vfs.registerVFS(sqlite3);
+      // Initialize IndexedDB backend
+      const backend = new IndexedDBBackend();
+      
+      // Create SQLiteFS instance
+      this.vfs = new SQLiteFS(backend, sqlite3);
+      
+      // Register the VFS
+      sqlite3.register_for_idb(this.vfs);
     } catch (error) {
       throw new StorageError(
         'Failed to set up IndexedDB VFS',
@@ -292,6 +303,7 @@ export class WebSQLiteService implements PlatformService {
     }
 
     try {
+      // Open database with absurd-sql
       this.db = await this.vfs.openDatabase('timesafari.db');
       await this.setupPragmas();
     } catch (error) {
@@ -312,6 +324,8 @@ export class WebSQLiteService implements PlatformService {
         PRAGMA synchronous = NORMAL;
         PRAGMA foreign_keys = ON;
         PRAGMA busy_timeout = 5000;
+        PRAGMA temp_store = MEMORY;
+        PRAGMA mmap_size = 30000000000;
       `);
     } catch (error) {
       throw new StorageError(
@@ -329,6 +343,34 @@ export class WebSQLiteService implements PlatformService {
     }
     this.initialized = false;
   }
+
+  // Example query method
+  async query<T>(sql: string, params: any[] = []): Promise<T[]> {
+    if (!this.db) {
+      throw new StorageError(
+        'Database not initialized',
+        StorageErrorCodes.INITIALIZATION_FAILED
+      );
+    }
+
+    try {
+      const stmt = this.db.prepare(sql);
+      const results: T[] = [];
+      
+      while (stmt.step()) {
+        results.push(stmt.getAsObject() as T);
+      }
+      
+      stmt.free();
+      return results;
+    } catch (error) {
+      throw new StorageError(
+        'Query failed',
+        StorageErrorCodes.QUERY_FAILED,
+        error
+      );
+    }
+  }
 }
 
 // Migration strategy for web platform
@@ -369,6 +411,14 @@ export class WebMigrationService {
         StorageErrorCodes.INITIALIZATION_FAILED
       );
     }
+
+    // Check absurd-sql compatibility
+    if (!window.indexedDB.databases) {
+      throw new StorageError(
+        'Browser does not support required IndexedDB features',
+        StorageErrorCodes.INITIALIZATION_FAILED
+      );
+    }
   }
 
   private async createBackup(): Promise<MigrationBackup> {
@@ -916,7 +966,7 @@ CREATE INDEX idx_settings_updated_at ON settings(updated_at);
 
 | Feature | Web | iOS | Android | Electron |
 |---------|-----|-----|---------|----------|
-| SQLite | wa-sqlite | SQLCipher | SQLCipher | SQLite |
+| SQLite | absurd-sql | SQLCipher | SQLCipher | SQLite |
 | Encryption | SQLCipher | SQLCipher | SQLCipher | SQLCipher |
 | Secure Storage | IndexedDB | Keychain | Keystore | Secure Storage |
 | Biometrics | No | Yes | Yes | No |
@@ -924,6 +974,8 @@ CREATE INDEX idx_settings_updated_at ON settings(updated_at);
 | Background Sync | No | Yes | Yes | Yes |
 | Storage Quota | Yes | No | No | No |
 | Multi-tab Support | Yes | N/A | N/A | Yes |
+| WAL Mode | Yes | Yes | Yes | Yes |
+| Atomic Transactions | Yes | Yes | Yes | Yes |
 
 ### D. Usage Examples