feat: claude-code backends + llamaswap provider + dogfood the CC engine (#3)

Phase 2: bump majordomo to latest and wire its new llamaswap provider
into gadfly's endpoint switches; add claude-code/sonnet to gadfly's own
dogfood swarm (pin :sha-86f12c1, map CLAUDE_CODE_OAUTH_TOKEN) so the
Phase-1 engine runs as a live competitor; document the Ollama-through-CC
ANTHROPIC_BASE_URL proxy path as example-only.

The 11-model swarm (incl. claude-code/sonnet) reviewed it; 52 findings
graded via the MCP. Folded in the two real ones: a llamaswap
endpointProvider test (caught by claude-code/sonnet, citing CLAUDE.md)
and adding "openai-compatible" to the provider error messages (gpt-oss).

gofmt clean, go vet quiet, go build + go test -race green.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Co-authored-by: Steve Dudenhoeffer <steve@stevedudenhoeffer.com>
Co-committed-by: Steve Dudenhoeffer <steve@stevedudenhoeffer.com>

cmd/gadfly/model.go

@@ -9,6 +9,7 @@ import (
 	llm "gitea.stevedudenhoeffer.com/steve/majordomo/llm"
 	"gitea.stevedudenhoeffer.com/steve/majordomo/provider/anthropic"
 	"gitea.stevedudenhoeffer.com/steve/majordomo/provider/google"
+	"gitea.stevedudenhoeffer.com/steve/majordomo/provider/llamaswap"
 	"gitea.stevedudenhoeffer.com/steve/majordomo/provider/ollama"
 	"gitea.stevedudenhoeffer.com/steve/majordomo/provider/openai"
 )
@@ -79,6 +80,12 @@ func resolveModel() (llm.Model, error) {
 			opts = append(opts, ollama.WithToken(apiKey))
 		}
 		return ollama.New(opts...).Model(model)
+	case "llamaswap":
+		opts := []llamaswap.Option{llamaswap.WithBaseURL(baseURL)}
+		if apiKey != "" {
+			opts = append(opts, llamaswap.WithToken(apiKey))
+		}
+		return llamaswap.New(opts...).Model(model)
 	case "foreman":
 		// foreman (gitea.stevedudenhoeffer.com/steve/foreman) is a native-Ollama
 		// queue daemon; the preset also smooths its non-streaming/long-poll
@@ -97,7 +104,7 @@ func resolveModel() (llm.Model, error) {
 		}
 		return google.New(opts...).Model(model)
 	default:
-		return nil, fmt.Errorf("GADFLY_BASE_URL is set but GADFLY_PROVIDER %q has no endpoint-override support (use openai/ollama/foreman/anthropic/google, or unset GADFLY_BASE_URL to resolve via majordomo)", provider)
+		return nil, fmt.Errorf("GADFLY_BASE_URL is set but GADFLY_PROVIDER %q has no endpoint-override support (use openai/openai-compatible/ollama/llamaswap/foreman/anthropic/google, or unset GADFLY_BASE_URL to resolve via majordomo)", provider)
 	}
 }
 
@@ -156,7 +163,7 @@ func modelProvider() string {
 //	    plaintext local Ollama (or foreman queue) works:
 //	        GADFLY_ENDPOINT_BIGBOX="ollama|http://192.168.1.50:11434"
 //	        GADFLY_MODEL=bigbox/qwen2.5-coder:7b
-//	    provider is one of ollama/foreman/openai/anthropic/google; "foreman"
+//	    provider is one of ollama/llamaswap/foreman/openai/anthropic/google; "foreman"
 //	    targets a foreman daemon (native Ollama on the wire):
 //	        GADFLY_ENDPOINT_M1="foreman|http://foreman-m1:8080|tok"
 //
@@ -215,6 +222,12 @@ func endpointProvider(name, raw string) (llm.Provider, error) {
 			opts = append(opts, ollama.WithToken(key))
 		}
 		return ollama.New(opts...), nil
+	case "llamaswap":
+		opts := []llamaswap.Option{llamaswap.WithName(name), llamaswap.WithBaseURL(baseURL)}
+		if key != "" {
+			opts = append(opts, llamaswap.WithToken(key))
+		}
+		return llamaswap.New(opts...), nil
 	case "foreman":
 		// foreman is native-Ollama on the wire; the preset additionally handles
 		// its non-streaming degradation. Unlike the HTTPS-only LLM_* foreman://
@@ -239,6 +252,6 @@ func endpointProvider(name, raw string) (llm.Provider, error) {
 		}
 		return google.New(opts...), nil
 	default:
-		return nil, fmt.Errorf("unknown provider %q (use ollama/foreman/openai/anthropic/google)", provider)
+		return nil, fmt.Errorf("unknown provider %q (use ollama/llamaswap/foreman/openai/openai-compatible/anthropic/google)", provider)
 	}
 }

cmd/gadfly/model_test.go

@@ -32,6 +32,20 @@ func TestEndpointProvider(t *testing.T) {
 			t.Fatalf("unexpected error: %v", err)
 		}
 	})
+	t.Run("llamaswap registers under its name", func(t *testing.T) {
+		p, err := endpointProvider("ls", "llamaswap|http://swap.lan:8080|tok")
+		if err != nil {
+			t.Fatalf("unexpected error: %v", err)
+		}
+		if p.Name() != "ls" {
+			t.Errorf("Name() = %q, want %q", p.Name(), "ls")
+		}
+	})
+	t.Run("llamaswap without token", func(t *testing.T) {
+		if _, err := endpointProvider("ls2", "llamaswap|http://swap.lan:8080"); err != nil {
+			t.Fatalf("unexpected error: %v", err)
+		}
+	})
 	for _, bad := range []string{"", "ollama", "noprovider-no-pipe", "mystery|http://x"} {
 		t.Run("rejects "+bad, func(t *testing.T) {
 			if _, err := endpointProvider("n", bad); err == nil {