feat(proxy): register traffic/uptime routes, spawn health checker, switch to dist/index.html

- Add traffic/uptime module declarations and route registrations
- Update include_str! from admin-ui/index.html to admin-ui/dist/index.html
- Spawn health checker after SharedState construction with backend URL snapshot
- Fix started_at field in cost/mod.rs test SharedState construction
- Unignore dist/ in .gitignore so compiled-in SPA works without a build step

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

.gitignore

@@ -43,4 +43,5 @@ scripts/.venv/
 
 # Admin UI build artifacts
 crates/proxy/admin-ui/node_modules/
-crates/proxy/admin-ui/dist/
+# dist/ is committed so `include_str!` works at compile time without a build step
+# crates/proxy/admin-ui/dist/

crates/proxy/src/admin/routes/mod.rs

@@ -6,6 +6,8 @@ pub mod keys;
 pub mod logs;
 pub mod mcp;
 pub mod models;
+pub mod traffic;
+pub mod uptime;
 
 use crate::admin::auth::{
     extract_csrf_cookie, generate_csrf_token, validate_admin_token, validate_csrf_tokens,
@@ -401,6 +403,8 @@ pub fn admin_router(shared: SharedState, token: Arc<zeroize::Zeroizing<String>>)
             "/admin/api/mcp-servers/{name}",
             delete(mcp::remove_mcp_server),
         )
+        .route("/admin/api/traffic", get(traffic::get_traffic))
+        .route("/admin/api/uptime", get(uptime::get_uptime))
         .with_state(shared.clone())
         // Innermost: CSRF check runs after auth succeeds.
         .layer(middleware::from_fn_with_state(
@@ -440,7 +444,7 @@ async fn health() -> Json<serde_json::Value> {
 }
 
 /// Serve the embedded SPA HTML with a per-request CSP nonce.
-static SPA_HTML: &str = include_str!("../../../admin-ui/index.html");
+static SPA_HTML: &str = include_str!("../../../admin-ui/dist/index.html");
 
 async fn serve_spa() -> axum::response::Response {
     // Generate a per-request nonce (128-bit, base64url-encoded).

crates/proxy/src/cost/mod.rs

@@ -441,6 +441,7 @@ mod tests {
                     .time_to_live(std::time::Duration::from_secs(86400))
                     .build(),
             ),
+            started_at: std::time::SystemTime::now(),
         };
 
         let vk_ctx = VirtualKeyContext {

crates/proxy/src/main.rs

@@ -497,6 +497,7 @@ async fn async_main(args: Vec<String>) {
                     .time_to_live(std::time::Duration::from_secs(86400))
                     .build(),
             ),
+            started_at: std::time::SystemTime::now(),
         };
 
         // Admin token: use env var or generate 256-bit random hex written to a file.
@@ -597,6 +598,16 @@ async fn async_main(args: Vec<String>) {
             }
         });
 
+        // Spawn background health checker with a snapshot of backend base URLs.
+        // base_url lives in BackendConfig (not RuntimeConfig), so we snapshot
+        // it here once at startup rather than storing it in SharedState.
+        let backend_urls: Vec<(String, String)> = multi_config
+            .backends
+            .iter()
+            .map(|(name, bc)| (name.clone(), bc.base_url.clone()))
+            .collect();
+        admin::health_check::spawn(shared.clone(), backend_urls);
+
         // Bind admin listener; spawned after the shutdown channel is created below.
         let admin_app = admin::routes::admin_router(shared.clone(), admin_token);
         let admin_bind = std::env::var("ADMIN_BIND").unwrap_or_else(|_| "127.0.0.1".into());