feat(qwen): let Qwen (and Kimi) join the swarm

majordomo now ships qwen and kimi as built-ins that ARE the openai client at
their own base URL, so "qwen/qwen3.8-max" works as a GADFLY_MODELS entry once
the key reaches the container. This wires up the parts that key has to pass
through.

Two provider switches had to learn the names, not one. resolveModel's
GADFLY_BASE_URL override was the obvious one; endpointProvider's
GADFLY_ENDPOINT_* parser is its sibling, and I fixed the first and missed the
second on the first pass — a config that resolves one way and errors the other
for no reason a user could guess. TestOpenAICompatProvidersResolveOnBothPaths
now asserts both from one table so the pair fails together; break-checked in
both directions.

QWEN_API_KEY (and KIMI_API_KEY) are declared as workflow_call secrets and
forwarded to the container, with gadfly's own stub forwarding QWEN_API_KEY so a
qwen entry can join the default swarm by editing GADFLY_DEFAULT_MODELS alone —
no workflow edit, no re-release.

The run.sh credential pre-flight is now a provider→variable table instead of an
ollama-cloud special case. Without it a forgotten key surfaces as five
identical per-lens agent failures naming no variable, and the operator reads a
stack trace to find out which secret they missed. Google stays out of the table
on purpose: it accepts either GOOGLE_API_KEY or GEMINI_API_KEY, and a one-var
entry would wrongly skip a correctly-configured run. Verified across 17
provider x key-state combinations, including that a wrong-provider key never
satisfies qwen (majordomo refuses cross-provider fallback) and that unkeyed
providers are never blocked.

Co-Authored-By: Claude Opus 5 (1M context) <[email protected]>

cmd/gadfly/model_test.go

@@ -68,6 +68,37 @@ func TestEndpointProvider(t *testing.T) {
 	}
 }
 
+// TestOpenAICompatProvidersResolveOnBothPaths pins the two provider switches
+// together. kimi and qwen are majordomo built-ins that ARE the openai client at
+// a different base URL, and two independent places have to know it:
+// resolveModel's GADFLY_BASE_URL override, and endpointProvider's
+// GADFLY_ENDPOINT_* parser. Adding a name to one and not the other yields a
+// provider that works when configured one way and errors the other, for no
+// reason a user could guess — which is exactly what happened here on the first
+// pass. Asserting both in one table is what makes the pair fail together.
+func TestOpenAICompatProvidersResolveOnBothPaths(t *testing.T) {
+	for _, provider := range []string{"openai", "openai-compatible", "kimi", "qwen"} {
+		t.Run(provider+" via GADFLY_ENDPOINT_*", func(t *testing.T) {
+			p, err := endpointProvider("ep", provider+"|https://host.example/v1|sk-x")
+			if err != nil {
+				t.Fatalf("endpointProvider(%q): %v", provider, err)
+			}
+			if p.Name() != "ep" {
+				t.Errorf("Name() = %q, want %q", p.Name(), "ep")
+			}
+		})
+		t.Run(provider+" via GADFLY_BASE_URL", func(t *testing.T) {
+			t.Setenv("GADFLY_PROVIDER", provider)
+			t.Setenv("GADFLY_BASE_URL", "https://host.example/v1")
+			t.Setenv("GADFLY_API_KEY", "sk-x")
+			t.Setenv("GADFLY_MODEL", "some-model")
+			if _, err := resolveModel(); err != nil {
+				t.Fatalf("resolveModel with GADFLY_PROVIDER=%q: %v", provider, err)
+			}
+		})
+	}
+}
+
 func TestBuildSpec(t *testing.T) {
 	tests := []struct {
 		name     string