refactor: replace orchestrator/verifier chain with direct LiteLLM calls

Drop the three-layer Claude subprocess orchestration (local model →
Claude verifier → cloud escalation). Skills now call LiteLLM directly
and return plain text to Claude Code, which decides what to do with it.

- Delete executor, orchestrator, verifier, result, attempts packages
- Simplify LiteLLMExecutor: Run(Request)→Result becomes Complete(model,sys,user)→(string,int64,error)
- Replace ExecutorFn with CompleteFunc in all 6 skill configs
- Rewrite all skill handlers to call Complete and return {"text","model","duration_ms"}
- Simplify config/models: remove Verifier/LlamaSwapURL, add ModelFor
- Bump version to v0.5.0

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

internal/skills/tdd/handlers_test.go

@@ -5,7 +5,6 @@ import (
 	"encoding/json"
 	"testing"
 
-	iexec "github.com/mathiasbq/supervisor/internal/exec"
 	"github.com/mathiasbq/supervisor/internal/session"
 	"github.com/mathiasbq/supervisor/internal/skills/tdd"
 	"github.com/stretchr/testify/assert"
@@ -14,8 +13,7 @@ import (
 
 func TestTDDSkillTools(t *testing.T) {
 	skill := tdd.New(tdd.Config{
-		SystemPrompt: "supervisor rules",
-		SkillPrompt:  "tdd rules",
+		SkillPrompt: "tdd rules",
 	})
 	tools := skill.Tools()
 	names := make([]string, len(tools))
@@ -26,19 +24,19 @@ func TestTDDSkillTools(t *testing.T) {
 }
 
 func TestTDDSkillHandleUnknown(t *testing.T) {
-	skill := tdd.New(tdd.Config{SystemPrompt: "s", SkillPrompt: "t"})
+	skill := tdd.New(tdd.Config{SkillPrompt: "t"})
 	_, err := skill.Handle(context.Background(), "tdd_unknown", json.RawMessage(`{}`))
 	assert.ErrorContains(t, err, "unknown tool")
 }
 
 func TestTDDRedRequiresProjectRoot(t *testing.T) {
-	skill := tdd.New(tdd.Config{SystemPrompt: "s", SkillPrompt: "t"})
+	skill := tdd.New(tdd.Config{SkillPrompt: "t"})
 	_, err := skill.Handle(context.Background(), "tdd_red", json.RawMessage(`{"spec":"add two numbers"}`))
 	assert.ErrorContains(t, err, "project_root")
 }
 
 func TestTDDRedRequiresSpec(t *testing.T) {
-	skill := tdd.New(tdd.Config{SystemPrompt: "s", SkillPrompt: "t"})
+	skill := tdd.New(tdd.Config{SkillPrompt: "t"})
 	_, err := skill.Handle(context.Background(), "tdd_red", json.RawMessage(`{"project_root":"/tmp/proj"}`))
 	assert.ErrorContains(t, err, "spec")
 }
@@ -51,35 +49,49 @@ func TestTDDGreenInjectsSessionHistory(t *testing.T) {
 		Message:  "wrote failing test for Foo",
 	}))
 
-	var capturedPrompt string
-	fakeFn := func(_ context.Context, req iexec.Request) (iexec.Result, error) {
-		capturedPrompt = req.TaskPrompt
-		return iexec.Result{Status: "pass", Phase: "green", Skill: "tdd", Verified: true, ModelUsed: "self", Message: "ok"}, nil
+	var capturedTask string
+	fakeFn := func(_ context.Context, _, _, user string) (string, int64, error) {
+		capturedTask = user
+		return "here is my suggestion", 100, nil
 	}
 
-	sk := tdd.New(tdd.Config{SkillPrompt: "tdd", ExecutorFn: fakeFn, SessionsDir: sessDir})
+	sk := tdd.New(tdd.Config{SkillPrompt: "tdd", CompleteFunc: fakeFn, SessionsDir: sessDir})
 	_, err := sk.Handle(context.Background(), "tdd_green", json.RawMessage(
 		`{"project_root":"/tmp","test_path":"internal/foo/foo_test.go","test_cmd":"go test ./...","session_id":"sess-1"}`,
 	))
 	require.NoError(t, err)
-	assert.Contains(t, capturedPrompt, "## Session history")
-	assert.Contains(t, capturedPrompt, "wrote failing test for Foo")
+	assert.Contains(t, capturedTask, "## Session history")
+	assert.Contains(t, capturedTask, "wrote failing test for Foo")
 }
 
 func TestTDDGreenNoHistoryWhenSessionIDEmpty(t *testing.T) {
-	var capturedPrompt string
-	fakeFn := func(_ context.Context, req iexec.Request) (iexec.Result, error) {
-		capturedPrompt = req.TaskPrompt
-		return iexec.Result{Status: "pass", Phase: "green", Skill: "tdd", Verified: true, ModelUsed: "self", Message: "ok"}, nil
+	var capturedTask string
+	fakeFn := func(_ context.Context, _, _, user string) (string, int64, error) {
+		capturedTask = user
+		return "suggestion", 50, nil
 	}
 
-	sk := tdd.New(tdd.Config{SkillPrompt: "tdd", ExecutorFn: fakeFn, SessionsDir: t.TempDir()})
+	sk := tdd.New(tdd.Config{SkillPrompt: "tdd", CompleteFunc: fakeFn, SessionsDir: t.TempDir()})
 	_, err := sk.Handle(context.Background(), "tdd_green", json.RawMessage(
 		`{"project_root":"/tmp","test_path":"internal/foo/foo_test.go"}`,
 	))
 	require.NoError(t, err)
-	assert.NotContains(t, capturedPrompt, "## Session history")
+	assert.NotContains(t, capturedTask, "## Session history")
 }
 
-// Ensure require is used (avoids import error).
-var _ = require.New
+func TestTDDGreenReturnsTextJSON(t *testing.T) {
+	fakeFn := func(_ context.Context, _, _, _ string) (string, int64, error) {
+		return "write a func that adds two ints", 42, nil
+	}
+
+	sk := tdd.New(tdd.Config{SkillPrompt: "tdd", CompleteFunc: fakeFn})
+	raw, err := sk.Handle(context.Background(), "tdd_green", json.RawMessage(
+		`{"project_root":"/tmp","test_path":"foo_test.go"}`,
+	))
+	require.NoError(t, err)
+
+	var result map[string]any
+	require.NoError(t, json.Unmarshal(raw, &result))
+	assert.Equal(t, "write a func that adds two ints", result["text"])
+	assert.Equal(t, float64(42), result["duration_ms"])
+}