[Router] Add composable scoring and eligibility policies (#37731)

Co-authored-by: inkcherry <mingzhi.liu@amd.com>

experimental/sgl-router/tests/proxy/cache_aware_input_ids.rs

@@ -12,10 +12,18 @@
 //!   doesn't render tool schemas, so its ids would diverge from the engine).
 //! * A request with multimodal (array) content → `input_ids` omitted (a text
 //!   tokenizer can't represent image content).
+//!
+//! The model id contains `deepseek-v4` so the tokenizer registry auto-attaches
+//! the built-in V4 chat encoder — the engine-equivalent path — without a
+//! template fixture.
 
 use axum::body::Body;
 use axum::http::{Request, StatusCode};
 use serde_json::{json, Value};
+use sgl_router::config::{
+    ActiveLoadConfig, CacheAwareConfig, Config, DiscoveryBackend, ModelConfig, ObservabilityConfig,
+    PolicyKind, ProxyConfig, ServerConfig, StaticUrlsDiscoveryConfig,
+};
 use sgl_router::discovery::{ModelId, WorkerId, WorkerMode, WorkerSpec};
 use sgl_router::policies::factory::build_registry;
 use sgl_router::policies::kv_events::{BlockSizeOracle, HashTree};
@@ -28,9 +36,35 @@ use std::sync::Arc;
 use std::time::Duration;
 use tower::ServiceExt;
 
-use crate::common::cache_aware_fixture::{config, MODEL};
 use crate::common::mock_worker::MockWorker;
 
+const MODEL: &str = "deepseek-v4-tiny";
+
+fn config() -> Config {
+    Config {
+        server: ServerConfig {
+            host: "0".into(),
+            port: 0,
+        },
+        observability: ObservabilityConfig::default(),
+        model: ModelConfig {
+            id: MODEL.into(),
+            tokenizer_path: "tests/fixtures/tiny_tokenizer.json".into(),
+            policy: PolicyKind::CacheAwareZmq,
+            circuit_breaker: None,
+            cache_aware: Some(CacheAwareConfig::default()),
+            sticky: None,
+            fused: None,
+            eligibility: None,
+        },
+        discovery: DiscoveryBackend::StaticUrls(StaticUrlsDiscoveryConfig {
+            urls: vec!["http://placeholder:0".into()],
+        }),
+        proxy: ProxyConfig::default(),
+        active_load: ActiveLoadConfig::default(),
+    }
+}
+
 fn build_ctx(url: String) -> Arc<AppContext> {
     let cfg = config();
     let tokenizers = Arc::new(TokenizerRegistry::load_from_config(&cfg).unwrap());