Create swatches for Svelte components.

A swatch is a live, and ideally editable, example of an element of the service. They serve as:

* Documentation: what is this element, how do you use it, what does it do?
* Demonstration: what does this element look like?
* Manual test scaffolding: when I change this element like _so_, what happens?

Swatches are collectively available under `/.swatch/` on a running instance. They do not require setup or login for simplicity's sake and because they don't _do_ anything that requires either of those things.

Swatches are manually curated. First, we lack the technical infrastructure needed to do this based on static analysis, and second, manual curation lets us include affordances like "interesting values," that would be tricky to express as part of the type or schema for the component. The tradeoff, however, is that they will fall out of step with the components if not reviewed regularly.

Swatches are _possible_ because we've gone to efforts to avoid global data access or direct side effects (including API requests) in our components, delegating that upwards to `+page`s and `+layout`s. However, the isolation is imperfect. For example, the swatch for `Conversation`, which renders the conversation sidebar entries, causes actual attempts to boot the app as browsers pre-fetch the links on mouseover, and clicking them will take the user to the "real" application because they really are links.

Merges swatch into main.

3 files changed, 11 insertions, 0 deletions

diff --git a/src/routes.rs b/src/routes.rs
index 49d9fb6..6993070 100644
--- a/src/routes.rs
+++ b/src/routes.rs
@@ -10,6 +10,7 @@ pub fn routes(app: &App) -> Router<App> {
     // UI routes that can be accessed before the administrator completes setup.
     let ui_bootstrap = Router::new()
         .route("/{*path}", get(ui::handlers::asset))
+        .route("/.swatch/{*path}", get(ui::handlers::swatch))
         .route("/setup", get(ui::handlers::setup));
 
     // UI routes that require the administrator to complete setup first.
diff --git a/src/ui/handlers/mod.rs b/src/ui/handlers/mod.rs
index ed0c14e..bcc65a1 100644
--- a/src/ui/handlers/mod.rs
+++ b/src/ui/handlers/mod.rs
@@ -5,6 +5,7 @@ mod invite;
 mod login;
 mod me;
 mod setup;
+mod swatch;
 
 pub use asset::handler as asset;
 pub use conversation::handler as conversation;
@@ -13,3 +14,4 @@ pub use invite::handler as invite;
 pub use login::handler as login;
 pub use me::handler as me;
 pub use setup::handler as setup;
+pub use swatch::handler as swatch;
diff --git a/src/ui/handlers/swatch.rs b/src/ui/handlers/swatch.rs
new file mode 100644
index 0000000..4562b04
--- /dev/null
+++ b/src/ui/handlers/swatch.rs
@@ -0,0 +1,8 @@
+use crate::{
+    error::Internal,
+    ui::assets::{Asset, Assets},
+};
+
+pub async fn handler() -> Result<Asset, Internal> {
+    Assets::index()
+}