Fix arg evaluation order + host interop gaps so reitit/selmer/honeysql run

Shaking the ring-app example's real library stack out against jolt surfaced a
batch of divergences from JVM Clojure, the biggest being evaluation order.

backend_scheme: call and recur arguments were emitted as bare Scheme operands,
so Chez's unspecified (right-to-left) order won out. Clojure evaluates left to
right, which selmer's reader loop relies on: (recur (add-node ... rdr) (read-char
rdr)) consumed a char early and dropped the first chars of every {{tag}}. Bind
operands to fresh temps in a let* (only when two or more can have side effects,
so hot calls over locals/consts stay un-wrapped). emit-ordered already did this
for collection literals; generalize it.

host-contract: syntax-quote now resolves the alias part of a qualified symbol
(impl/foo -> clojure.tools.logging.impl/foo) instead of leaving it bare, which
limped along via short-name matching until two loaded namespaces (reitit.impl,
clojure.tools.logging.impl) shared the short name and it broke.

collections: key-hash masks with bitwise-and, not fxand — jolt-hash is set!-
decorated per type (records return their own hash) and Chez's equal-hash can be a
bignum, so a key's hash isn't always a fixnum.

seq: even?/odd? handle bignums (JVM accepts any integer; the fxand crashed).

records: Keyword/Symbol .sym/.getName/.toString (honeysql's :clj branch reads
(.sym k)); Throwable .getMessage/.toString over a Chez condition.

host-static: __register-class-ctor!/__register-class-statics! so a host shim
(reitit.trie-jolt) can mirror a Java class.

natives-str: String.intern returns the string.

sqlite: jdbc.core fetch/fetch-one kebab-case column keys (the jolt-lang/db
convention; created_at -> :created-at).

io: a relative io/file path resolves against JOLT_PWD (the user's cwd), not the
repo root the launcher cd'd to — matches JVM cwd semantics, so config.edn loads.

cli: render an uncaught jolt throw (ex-info message + ex-data, or a condition)
instead of Chez's opaque "non-condition value" dump.

host/chez/io.ss

@@ -20,9 +20,19 @@
 ;; path string of any value: a jfile -> its path, else its str rendering.
 (define (file-path-of x) (if (jfile? x) (jfile-path x) (jolt-str-render-one x)))
 
+;; A user-facing relative path resolves against JOLT_PWD — the user's cwd before
+;; the launcher cd'd to the jolt repo root — matching the JVM, where io/file is
+;; cwd-relative. (io/resource builds jfiles from the source roots directly, so it
+;; isn't routed through here.)
+(define (project-relative p)
+  (if (or (= (string-length p) 0) (char=? (string-ref p 0) #\/))
+      p
+      (let ((pwd (getenv "JOLT_PWD")))
+        (if (and pwd (> (string-length pwd) 0)) (string-append pwd "/" p) p))))
+
 ;; (io/file path) / (io/file parent child) — join children with "/".
 (define (jolt-make-file path . rest)
-  (let loop ((p (file-path-of path)) (cs rest))
+  (let loop ((p (project-relative (file-path-of path))) (cs rest))
     (if (null? cs) (make-jfile p)
         (loop (string-append p "/" (file-path-of (car cs))) (cdr cs)))))