# Change: Add Flexible Deployment Options

## Why
Enterprise deployment environments vary significantly. Some networks block MySQL port 33306, preventing access to cloud databases. Additionally, the current portable executable extracts to a random folder in `%TEMP%`, causing Windows Defender warnings on each launch and potential permission issues.

## What Changes
- **SQLite database support** - Allow choosing between MySQL (cloud) and SQLite (local) databases at build time via `--database-type` parameter
- **Fixed portable extraction path** - Configure `unpackDirName` to use a predictable folder name instead of random UUID

## Impact
- Affected specs: `embedded-backend` (modified)
- Affected code:
  - `client/config.json` - Add `database.type` and `database.sqlitePath` fields
  - `client/package.json` - Add `unpackDirName` to portable configuration
  - `backend/app/config.py` - Add `DB_TYPE` and `SQLITE_PATH` settings
  - `backend/app/database.py` - Conditional SQLite/MySQL initialization
  - `backend/run_server.py` - Pass database type environment variables
  - `scripts/build-client.bat` - Add `--database-type` parameter