Add (param :as type) annotations to defcomp params across all services and templates

Annotates ~500 defcomp params across 62 files: market (5), blog (7), cart (5),
events (3), federation (4), account (3), orders (2), shared templates (11),
sx docs (14), plus remaining spec fn params (z3, test-framework, adapter-dom,
adapter-async, engine, eval). Total annotations in codebase: 1043.

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

shared/sx/ref/test-framework.sx

@@ -57,7 +57,7 @@
     (assert (nil? val) (str "Expected nil but got " (str val)))))
 
 (define assert-type
-  (fn (expected-type val)
+  (fn ((expected-type :as string) val)
     (let ((actual-type
             (if (nil? val) "nil"
               (if (boolean? val) "boolean"
@@ -70,17 +70,17 @@
         (str "Expected type " expected-type " but got " actual-type)))))
 
 (define assert-length
-  (fn (expected-len col)
+  (fn ((expected-len :as number) (col :as list))
     (assert (= (len col) expected-len)
       (str "Expected length " expected-len " but got " (len col)))))
 
 (define assert-contains
-  (fn (item col)
+  (fn (item (col :as list))
     (assert (some (fn (x) (equal? x item)) col)
       (str "Expected collection to contain " (str item)))))
 
 (define assert-throws
-  (fn (thunk)
+  (fn ((thunk :as lambda))
     (let ((result (try-call thunk)))
       (assert (not (get result "ok"))
         "Expected an error to be thrown but none was"))))