Phase 1 complete: Var/Namespace system with binding macro fix

Root causes:
- core-binding used tuples instead of arrays for call forms.
  Evaluator treats tuples as literal vectors, so calls failed.
  Fixed with @[...] and proper (push-thread-bindings frame) forms.
- try handler: finally only ran on error, not success.
  Fixed to run finally on both paths.
- ns accessors: all-ns, remove-ns, create-ns, the-ns, ns-interns,
  ns-aliases, ns-imports-fn added to types.janet
- ns form: :require/:refer, :use, :refer-clojure/:exclude, :import
- eval-require: :refer support
- All 317 tests pass, 0 failures

test/compiler-test.janet

@@ -250,3 +250,14 @@
 (print "  passed")
 
 (print "\nAll Phase 1 tests passed!")
+
+(print "16: binding macro...")
+(let [ctx (init)]
+  (eval-string ctx "(def ^:dynamic *x* 10)")
+  (assert (= 10 (eval-string ctx "*x*")) "dynamic var default")
+  (assert (= 99 (eval-string ctx "(binding [*x* 99] *x*)")) "binding rebinds")
+  (assert (= 10 (eval-string ctx "*x*")) "binding restored"))
+
+(print "  passed")
+
+(print "\nAll Phase 1 tests passed!")