fix: sqlite lock error (#2672)

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## Changes

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<!-- This is an auto-generated comment: release notes by coderabbit.ai -->

## Summary by CodeRabbit

* **Bug Fixes**
  * Improved concurrency handling for image downloads, preventing duplicate downloads and enhancing performance.
  * Enhanced image pruning process for more efficient removal of outdated images.

* **Refactor**
  * Updated internal mechanisms for managing ongoing downloads to use a more robust locking strategy.
  * Simplified and optimized SQL queries related to image cache management.

* **Chores**
  * Updated database connection settings for better performance and reliability.
  * Removed an unused dependency to streamline the application.

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Author: MasterPtato

packages/edge/infra/client/manager/Cargo.toml

@@ -30,7 +30,6 @@ rand = "0.8"
 rand_chacha = "0.3.1"
 reqwest = { version = "0.12", default-features = false, features = ["stream", "rustls-tls", "json"] }
 rivet-logs.workspace = true
-scc = "2.3.4"
 serde = { version = "1.0.195", features = ["derive"] }
 serde_json = "1.0.111"
 serde_yaml = "0.9.34"

packages/edge/infra/client/manager/src/ctx.rs

@@ -975,8 +975,7 @@ impl Ctx {
 		// Delete entries that aren't in our valid images table
 		let deleted = sqlx::query(indoc!(
 			"
-			DELETE
-			FROM images_cache
+			DELETE FROM images_cache
 			WHERE image_id NOT IN (
 				SELECT image_id FROM __valid_images
 			)