Add Rust server

Owns the database, PIN rotation and all LiveKit token minting. Kiosk
registration, session-stable joins, admin auth, layouts, branding, media
uploads and the hosted installer script.

server/src/routes/install.rs

@@ -0,0 +1,45 @@
+use axum::extract::State;
+use axum::http::header::{HeaderMap, CONTENT_TYPE};
+use axum::http::HeaderValue;
+use axum::response::{IntoResponse, Response};
+
+use crate::state::AppState;
+
+const INSTALL_SCRIPT: &str = include_str!("../../assets/install.sh");
+const SERVER_URL_PLACEHOLDER: &str = "__PISTATION_SERVER_URL__";
+
+pub async fn install_script(State(state): State<AppState>, headers: HeaderMap) -> Response {
+    let server_url = resolve_server_url(&state, &headers);
+    let body = INSTALL_SCRIPT.replace(SERVER_URL_PLACEHOLDER, &server_url);
+
+    let mut response = body.into_response();
+    response.headers_mut().insert(
+        CONTENT_TYPE,
+        HeaderValue::from_static("text/x-shellscript; charset=utf-8"),
+    );
+    response
+}
+
+fn resolve_server_url(state: &AppState, headers: &HeaderMap) -> String {
+    let host = header_value(headers, "x-forwarded-host").or_else(|| header_value(headers, "host"));
+
+    if let Some(host) = host {
+        let scheme =
+            header_value(headers, "x-forwarded-proto").unwrap_or_else(|| "http".to_string());
+        return format!("{scheme}://{host}");
+    }
+
+    if !state.config.public_api_url.is_empty() {
+        return state.config.public_api_url.trim_end_matches('/').to_string();
+    }
+
+    "http://localhost:8080".to_string()
+}
+
+fn header_value(headers: &HeaderMap, name: &str) -> Option<String> {
+    headers
+        .get(name)
+        .and_then(|value| value.to_str().ok())
+        .map(|value| value.split(',').next().unwrap_or(value).trim().to_string())
+        .filter(|value| !value.is_empty())
+}