Draft: feat: Implement Sqflite database

First benchmarks:

• Device: iOS Emulator
• App: FluffyChat latest
• Account with around 100 rooms on Synapse

Using sqflite_cipher and HiveCipher for encryption.

Initial Sync:

HiveCollectionsDatabase

flutter: [Matrix] Benchmark: Process sync -> 4942 ms (4300 items, 1.1493023255813954 ms/item)

SQFlite

flutter: [Matrix] Benchmark: Process sync -> 4733 ms (4304 items, 1.099674721189591 ms/item)

App Start:

HiveCollectionsDatabase

flutter: [Matrix] Benchmark: Get all account data from store -> 42 ms flutter: [Matrix] Benchmark: Get all user device keys from store -> 154 ms flutter: [Matrix] Benchmark: Get room list from store -> 710 ms

SQFlite

flutter: [Matrix] Benchmark: Get all account data from store -> 96 ms flutter: [Matrix] Benchmark: Get all user device keys from store -> 387 ms flutter: [Matrix] Benchmark: Get room list from store -> 490 ms

TODOS:

• Implement POC FluffyChat implementation
• Implement Database encryption
• Implement encrypted file storage
• Test on web
• Implement transactions (should increase performance of initial sync by a lot)
• Implement type adapters and get rid of inperformant row.toJson() and json.toRow() methods (should increase overall performance a little bit)
• Investigate more performant sort_order solution (should increase performance of syncs)