Add static CPU model and core count to CPU collector

- Collect CPU model name and core count from /proc/cpuinfo
- Only collect once at startup (check if fields already set)
- Display below C-state row in dashboard CPU section
- Move CPU info collection from NixOS collector to CPU collector

agent/src/collectors/cpu.rs

@@ -119,6 +119,34 @@ impl CpuCollector {
         utils::parse_u64(content.trim())
     }
 
+    /// Collect static CPU information from /proc/cpuinfo (only once at startup)
+    async fn collect_cpu_info(&self, agent_data: &mut AgentData) -> Result<(), CollectorError> {
+        let content = utils::read_proc_file("/proc/cpuinfo")?;
+
+        let mut model_name: Option<String> = None;
+        let mut core_count: u32 = 0;
+
+        for line in content.lines() {
+            if line.starts_with("model name") {
+                if let Some(colon_pos) = line.find(':') {
+                    let name = line[colon_pos + 1..].trim().to_string();
+                    if model_name.is_none() {
+                        model_name = Some(name);
+                    }
+                }
+            } else if line.starts_with("processor") {
+                core_count += 1;
+            }
+        }
+
+        agent_data.system.cpu.model_name = model_name;
+        if core_count > 0 {
+            agent_data.system.cpu.core_count = Some(core_count);
+        }
+
+        Ok(())
+    }
+
     /// Collect CPU C-state (idle depth) and populate AgentData with top 3 C-states by usage
     async fn collect_cstate(&self, agent_data: &mut AgentData) -> Result<(), CollectorError> {
         // Read C-state usage from first CPU (representative of overall system)
@@ -192,6 +220,11 @@ impl Collector for CpuCollector {
         debug!("Collecting CPU metrics");
         let start = std::time::Instant::now();
 
+        // Collect static CPU info (only once at startup)
+        if agent_data.system.cpu.model_name.is_none() || agent_data.system.cpu.core_count.is_none() {
+            self.collect_cpu_info(agent_data).await?;
+        }
+
         // Collect load averages (always available)
         self.collect_load_averages(agent_data).await?;