feat: scaffold cortex workspace

Rust reverse-proxy for multi-node mistral.rs inference clusters.
Includes crate structure (cortex-core, cortex-gateway, cortex-agent,
cortex-cli), config loading, OpenAI/Anthropic translation stubs,
model routing, eviction, polling, and streaming proxy scaffolding.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

crates/cortex-core/src/config.rs

@@ -0,0 +1,79 @@
+use figment::{
+    Figment,
+    providers::{Env, Format, Toml},
+};
+use serde::{Deserialize, Serialize};
+use std::path::Path;
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct GatewayConfig {
+    pub gateway: GatewaySettings,
+    pub eviction: EvictionSettings,
+    pub nodes: Vec<NodeConfig>,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct GatewaySettings {
+    /// Address to listen on for API requests (e.g. "0.0.0.0:8000")
+    pub listen: String,
+    /// Address to listen on for Prometheus metrics (e.g. "0.0.0.0:9100")
+    pub metrics_listen: String,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct EvictionSettings {
+    /// Eviction strategy: "lru" or "priority"
+    pub strategy: EvictionStrategy,
+    /// Restart the mistralrs process after this many load/unload cycles
+    /// to reclaim fragmented VRAM. 0 = never.
+    #[serde(default)]
+    pub defrag_after_cycles: u32,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+#[serde(rename_all = "lowercase")]
+pub enum EvictionStrategy {
+    Lru,
+    Priority,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct NodeConfig {
+    /// Human-readable node name (e.g. "gpu-large")
+    pub name: String,
+    /// Base URL of the mistralrs HTTP server (e.g. "http://gpu-large.internal:8080")
+    pub endpoint: String,
+    /// Total VRAM in MB across all GPUs on this node
+    pub vram_mb: u64,
+    /// Model IDs that should never be evicted from this node
+    #[serde(default)]
+    pub pinned: Vec<String>,
+}
+
+impl GatewayConfig {
+    /// Load configuration from a TOML file, with environment variable overrides.
+    /// Env vars are prefixed with `CORTEX_` and use `__` as a separator
+    /// (e.g. `CORTEX_GATEWAY__LISTEN=0.0.0.0:9000`).
+    pub fn load(path: impl AsRef<Path>) -> Result<Self, figment::Error> {
+        Figment::new()
+            .merge(Toml::file(path))
+            .merge(Env::prefixed("CORTEX_").split("__"))
+            .extract()
+    }
+}
+
+impl Default for GatewayConfig {
+    fn default() -> Self {
+        Self {
+            gateway: GatewaySettings {
+                listen: "0.0.0.0:8000".into(),
+                metrics_listen: "0.0.0.0:9100".into(),
+            },
+            eviction: EvictionSettings {
+                strategy: EvictionStrategy::Lru,
+                defrag_after_cycles: 50,
+            },
+            nodes: vec![],
+        }
+    }
+}