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/retrospective/handlers.go

@@ -7,7 +7,6 @@ import (
 	"fmt"
 	"time"
 
-	iexec "github.com/mathiasbq/supervisor/internal/exec"
 	"github.com/mathiasbq/supervisor/internal/session"
 )
 
@@ -34,7 +33,6 @@ func (s *Skill) Handle(ctx context.Context, tool string, args json.RawMessage) (
 		model = s.cfg.DefaultModel
 	}
 
-	// Read session log entries (empty slice if no log exists yet).
 	entries, err := session.Read(s.cfg.SessionsDir, a.SessionID)
 	if err != nil {
 		return nil, fmt.Errorf("read session log: %w", err)
@@ -46,39 +44,33 @@ func (s *Skill) Handle(ctx context.Context, tool string, args json.RawMessage) (
 	}
 
 	taskPrompt := fmt.Sprintf(
-		"SESSION_ID: %s\n\nSESSION_LOG:\n%s\n\nReview this session log. Identify what is novel or worth preserving as organizational knowledge. Write structured entries to brain/raw/ via brain_write. Return JSON result when done.",
+		"SESSION_ID: %s\n\nSESSION_LOG:\n%s\n\nReview this session log. Identify what is novel or worth preserving as organizational knowledge. Provide structured insights.",
 		a.SessionID, string(logJSON),
 	)
 
-	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:  taskPrompt,
-		Model:       model,
-		Tools:       "Bash,Read,Write",
-	})
+	text, dur, err := s.cfg.CompleteFunc(ctx, model, s.cfg.SkillPrompt, taskPrompt)
 	if err != nil {
-		return nil, fmt.Errorf("retrospective worker: %w", err)
+		return nil, fmt.Errorf("retrospective model: %w", err)
 	}
 
+	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:       "retrospective",
 		Phase:       "retrospective",
-		Attempts:    session.AttemptsFrom(result.Attempts),
-		FinalStatus: result.Status,
-		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})
 }