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/spec/handlers.go

@@ -8,7 +8,6 @@ import (
 	"time"
 
 	"github.com/mathiasbq/supervisor/internal/brain"
-	iexec "github.com/mathiasbq/supervisor/internal/exec"
 	"github.com/mathiasbq/supervisor/internal/session"
 )
 
@@ -57,39 +56,32 @@ func (s *Skill) Handle(ctx context.Context, tool string, args json.RawMessage) (
 		task = brainCtx + "\n---\n\n" + task
 	}
 
-	if s.cfg.ExecutorFn == nil {
+	if s.cfg.CompleteFunc == nil {
 		return nil, fmt.Errorf("no executor configured")
 	}
 	t0 := time.Now()
-	result, err := s.cfg.ExecutorFn(ctx, iexec.Request{
-		SkillPrompt: s.cfg.SkillPrompt,
-		TaskPrompt:  task,
-		Model:       model,
-		Tools:       "Read,Write",
-	})
+	text, dur, err := s.cfg.CompleteFunc(ctx, model, s.cfg.SkillPrompt, task)
 	if err != nil {
 		return nil, err
 	}
 
 	if a.SessionID != "" && s.cfg.SessionsDir != "" {
+		msg := text
+		if len(msg) > 200 {
+			msg = msg[:200]
+		}
 		_ = session.Append(s.cfg.SessionsDir, a.SessionID, session.Entry{
 			SessionID:   a.SessionID,
 			Timestamp:   time.Now(),
 			Skill:       "spec",
 			Phase:       "spec",
 			ProjectRoot: a.ProjectRoot,
-			Attempts:    session.AttemptsFrom(result.Attempts),
-			FinalStatus: result.Status,
-			FilePath:    result.FilePath,
-			ModelUsed:   result.ModelUsed,
+			FinalStatus: "ok",
+			ModelUsed:   model,
 			DurationMs:  time.Since(t0).Milliseconds(),
-			Message:     result.Message,
+			Message:     msg,
 		})
 	}
 
-	b, err := json.Marshal(result)
-	if err != nil {
-		return nil, fmt.Errorf("marshal result: %w", err)
-	}
-	return b, nil
+	return json.Marshal(map[string]any{"text": text, "model": model, "duration_ms": dur})
 }