fix(canvas): unblock deploy when runtime has no required env vars

AllKeysModal and ProviderPickerModal guarded allSaved with
entries.length > 0, so when a runtime (e.g. openclaw) declares
no required_env and providers=[], the entries array is empty and
allSaved=false — the Deploy button stayed disabled with no way
to proceed.

Fix: drop the length guard. [].every(fn) is vacuously true per
the JS spec, so allSaved correctly reflects "nothing required,
nothing missing" when the template needs no API keys.

canvas/src/components/MissingKeysModal.tsx

@@ -344,7 +344,7 @@ function ProviderPickerModal({
   // wrapper's bounds instead of the viewport.
   if (typeof document === "undefined") return null;
 
-  const allSaved = entries.length > 0 && entries.every((e) => e.saved);
+  const allSaved = entries.every((e) => e.saved); // vacuously true for [] — no required keys means deploy is always ready
   const anySaving = entries.some((e) => e.saving);
   const runtimeLabel = runtime
     .replace(/[-_]/g, " ")
@@ -616,7 +616,7 @@ function AllKeysModal({
   if (!open) return null;
   if (typeof document === "undefined") return null;
 
-  const allSaved = entries.length > 0 && entries.every((e) => e.saved);
+  const allSaved = entries.every((e) => e.saved); // vacuously true for [] — no required keys means deploy is always ready
   const anySaving = entries.some((e) => e.saving);
   const runtimeLabel = runtime
     .replace(/[-_]/g, " ")