Expose the web server as an embeddable Axum router

crates-server/yaak-web/Cargo.toml

@@ -7,7 +7,7 @@ description = "The server behind Yaak in the browser: executes sends, and can se
 
 # The send engine (yaak-http) and the model types it speaks (yaak-models, for
 # HttpRequest / Cookie / HttpResponseEventData). Deliberately NOT yaak (the
-# render + storage orchestration), yaak-plugins, or the RPC router: this binary
+# render + storage orchestration), yaak-plugins, or the RPC router: this crate
 # opens no database, runs no plugins, and renders nothing. yaak-models comes
 # along only because yaak-http's types are its types; nothing here calls into
 # its query layer.
@@ -34,3 +34,7 @@ url = "2"
 uuid = { version = "1", features = ["v4"] }
 yaak-http = { workspace = true }
 yaak-models = { workspace = true }
+
+[dev-dependencies]
+tempfile = "3"
+tower = { version = "0.5", features = ["util"] }