Create Initial Database Schema for Tasks. (#1)

Create migration scripts for this and initial Task DB Model in rust along with unit tests.

Reviewed-on: #1
Co-authored-by: Drew Galbraith <drew@tiramisu.one>
Co-committed-by: Drew Galbraith <drew@tiramisu.one>

backend/src/database/connection.rs

@@ -0,0 +1,45 @@
+use anyhow::Result;
+use sqlx::{SqlitePool, sqlite::SqliteConnectOptions};
+use std::str::FromStr;
+
+/// Database configuration
+pub struct DatabaseConfig {
+    pub database_url: String,
+}
+
+impl Default for DatabaseConfig {
+    fn default() -> Self {
+        Self {
+            database_url: "sqlite:local.db".to_string(),
+        }
+    }
+}
+
+/// Create a SQLx connection pool
+pub async fn create_pool(config: &DatabaseConfig) -> Result<SqlitePool> {
+    let options = SqliteConnectOptions::from_str(&config.database_url)?.create_if_missing(true);
+
+    let pool = SqlitePool::connect_with(options).await?;
+
+    sqlx::migrate!("./migrations").run(&pool).await?;
+
+    Ok(pool)
+}
+
+/// Initialize database with connection pool
+pub async fn initialize_database() -> Result<SqlitePool> {
+    let config = DatabaseConfig::default();
+    create_pool(&config).await
+}
+
+#[cfg(test)]
+pub async fn create_test_pool() -> Result<SqlitePool> {
+    let options = SqliteConnectOptions::from_str("sqlite::memory:")?.create_if_missing(true);
+
+    let pool = SqlitePool::connect_with(options).await?;
+
+    sqlx::migrate!("./migrations").run(&pool).await?;
+
+    Ok(pool)
+}
+