feat: add HAProxy log ingestion server

- Introduced a new Rust-based service for ingesting HAProxy logs, including the necessary database schema and API endpoints.
- Implemented database interactions for managing source status, inserting events, and handling ingestion batches.
- Added validation for incoming log batches to ensure data integrity.
- Configured systemd service for the HAProxy ingestion server with appropriate security settings.
- Updated firewall rules to allow traffic on the ingestion server's port (8444).
- Created necessary PostgreSQL database and user configurations for the ingestion service.

rust/haproxy_ingest_server/Cargo.toml

@@ -0,0 +1,29 @@
+[package]
+name = "haproxy-ingest-server"
+version = "0.1.0"
+edition = "2024"
+description = "HAProxy log ingestion API"
+license = "MIT"
+
+[lints]
+workspace = true
+
+[dependencies]
+anyhow.workspace = true
+axum.workspace = true
+bytes.workspace = true
+chrono = { workspace = true, features = ["serde"] }
+clap.workspace = true
+haproxy-ingest-proto = { path = "../haproxy_ingest_proto" }
+hex.workspace = true
+prost.workspace = true
+serde.workspace = true
+sha2.workspace = true
+sqlx.workspace = true
+subtle.workspace = true
+thiserror.workspace = true
+tokio.workspace = true
+tower-http.workspace = true
+tracing.workspace = true
+tracing-subscriber.workspace = true
+zstd.workspace = true