feat(telemetry): Implement structured telemetry logging and reporting

Adds comprehensive client-side telemetry capabilities for usage, errors, and performance metrics. This includes integrating OpenTelemetry standards into both the frontend (Svelte) and backend (Tauri/Rust) layers to capture events, spans, and system resource utilization.

The implementation ensures that all collected data is privacy-filtered by design, explicitly excluding sensitive information like repository paths, credentials, source code, or email addresses from being logged.

- Updates README with detailed SigNoz telemetry guide
- Adds process metrics collection (CPU/Memory) in Rust backend
- Exposes `setTelemetryEnabled` state management to the frontend

src-tauri/Cargo.toml

@@ -22,6 +22,8 @@ keyring = { version = "3", features = ["apple-native", "windows-native", "async-
 commit_ai = { path = "crates/commit_ai" }
 tokio = "1.52.3"
 log = "0.4"
+reqwest = { version = "0.12", default-features = false, features = ["blocking", "json", "rustls-tls"] }
+sysinfo = { version = "=0.38.3", default-features = false, features = ["system"] }
 
 [build-dependencies]
 tauri-build = { version = "2", features = [] }