refactor appState and proxy

[ChuckHend]

• separate the proxy logic from server
• move cache update process into its own module
• creates appState struct

[Copilot]

Pull Request Overview

This PR refactors the application architecture by consolidating state management into a single AppState struct and separating proxy logic from the main server module.

• Creates a centralized AppState struct to manage database pools, job cache, worker health, and configuration
• Extracts cache management functionality into a dedicated cache module
• Moves PostgreSQL proxy startup logic from main server to the proxy crate

Reviewed Changes

Copilot reviewed 11 out of 12 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
server/src/app_state.rs	New centralized application state management struct
server/src/cache.rs	Extracted cache synchronization and job notification logic
server/src/main.rs	Simplified main function using new AppState pattern
server/src/routes/*.rs	Updated route handlers to use AppState instead of individual dependencies
proxy/src/proxy.rs	Added proxy startup function moved from server main
*/Cargo.toml	Updated tracing dependencies to use workspace versions

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[Copilot]

Using unwrap() on URL parsing results can cause panics. Consider using proper error handling with meaningful error messages for when host or port are missing from the URL.

Suggested change

	let postgres_port = url.port().unwrap();
	let postgres_port = url
	.port()
	.ok_or("Database URL is missing a port")?;