feature: host-meta file for templated links

src/http/handle_host_meta.rs

···
+use axum::Json;
+use serde_json::json;
+
+pub(super) async fn handle_host_meta() -> Json<serde_json::Value> {
+    Json(json!({
+        "links": [
+            {
+                "rel": "https://hopper.at/rel/link",
+                "template": "https://smokesignal.events/{authority}/{rkey}",
+                "properties": {
+                    "https://atproto.com/ns/collection": "community.lexicon.calendar.event"
+                }
+            },
+            {
+                "rel": "https://hopper.at/rel/link",
+                "template": "https://smokesignal.events/{authority}",
+                "properties": {
+                    "https://atproto.com/ns/collection": "events.smokesignal.profile"
+                }
+            }
+        ]
+    }))
+}

src/http/mod.rs

···
 pub mod handle_export_ics;
 pub mod handle_export_rsvps;
 pub mod handle_health;
+pub mod handle_host_meta;
 pub mod handle_import;
 pub mod handle_index;
 pub mod handle_oauth_aip_callback;

src/http/server.rs

···
     handle_export_ics::handle_export_ics,
     handle_export_rsvps::handle_export_rsvps,
     handle_health::{handle_alive, handle_ready, handle_started},
+    handle_host_meta::handle_host_meta,
     handle_import::{handle_import, handle_import_submit},
     handle_index::handle_index,
     handle_oauth_logout::handle_logout,
···
         .route("/cookie-policy", get(handle_cookie_policy))
         .route("/acknowledgement", get(handle_acknowledgement))
         .route("/.well-known/did.json", get(handle_wellknown_did_web))
+        .route("/asdasd", get(handle_host_meta))
         .route("/_ready", get(handle_ready))
         .route("/_alive", get(handle_alive))
         .route("/_started", get(handle_started))