cleanup: supprime le code mort des skills (fondus dans la memoire)

- supprime skills.go (Skill, ListSkills, SkillContent, SaveSkill, AppendSkill,
  DeleteSkill, safeSkillDir, skillsSystemPrompt : plus aucun appelant)
- retire les handlers/routes /api/skill, /api/skill/save, /api/skill/delete
  (aucun client : ni UI locale, ni ajean-app, ni jean-relay)
- conserve les alias retro-compat /api/skills(/toggle) -> handleAgent, la
  migration migrateSkillsToMemory et legacySkillsFlag

memory.go

@@ -255,7 +255,7 @@ func MemContent(name string) string {
 
 // MemSave écrit (crée ou écrase) une page mémoire. Si old est fourni et diffère
 // du nouveau nom, l'ancienne page est renommée (supprimée). Utilisé par l'éditeur
-// web — pendant de SaveSkill.
+// web.
 func MemSave(name, old, content string) error {
 	if old != "" {
 		if oldFn, e1 := memFileName(old); e1 == nil {

skills.go

@@ -1,155 +0,0 @@
-package main
-
-import (
-	"fmt"
-	"os"
-	"path/filepath"
-	"regexp"
-	"sort"
-	"strings"
-)
-
-type Skill struct {
-	Name    string
-	Desc    string // first non-empty line, with leading #'s stripped
-	Content string
-}
-
-// ListSkills walks SKILLS/<name>/SKILL.md, returning name+desc+full content.
-func ListSkills() []Skill {
-	entries, err := os.ReadDir(skillsDir())
-	if err != nil {
-		return nil
-	}
-	out := []Skill{}
-	for _, e := range entries {
-		if !e.IsDir() || strings.HasPrefix(e.Name(), ".") {
-			continue
-		}
-		f := filepath.Join(skillsDir(), e.Name(), "SKILL.md")
-		b, err := os.ReadFile(f)
-		if err != nil {
-			continue
-		}
-		content := string(b)
-		desc := ""
-		for _, line := range strings.Split(content, "\n") {
-			s := strings.TrimSpace(strings.TrimLeft(strings.TrimSpace(line), "#"))
-			if s != "" {
-				desc = s
-				break
-			}
-		}
-		out = append(out, Skill{Name: e.Name(), Desc: desc, Content: content})
-	}
-	sort.Slice(out, func(i, j int) bool { return out[i].Name < out[j].Name })
-	return out
-}
-
-var skillNameRe = regexp.MustCompile(`^[A-Za-z0-9._-]+$`)
-
-// safeSkillDir validates and returns the on-disk path for a skill directory.
-func safeSkillDir(name string) (string, error) {
-	if !skillNameRe.MatchString(name) {
-		return "", fmt.Errorf("nom invalide (alphanum, ._-)")
-	}
-	root, err := filepath.Abs(skillsDir())
-	if err != nil {
-		return "", err
-	}
-	p := filepath.Join(root, name)
-	abs, err := filepath.Abs(p)
-	if err != nil {
-		return "", err
-	}
-	if !strings.HasPrefix(abs, root+string(filepath.Separator)) {
-		return "", fmt.Errorf("path invalide")
-	}
-	return abs, nil
-}
-
-// SkillContent loads SKILL.md for the given name (used by the read_skill tool).
-func SkillContent(name string) string {
-	d, err := safeSkillDir(name)
-	if err != nil {
-		return ""
-	}
-	b, err := os.ReadFile(filepath.Join(d, "SKILL.md"))
-	if err != nil {
-		return ""
-	}
-	return string(b)
-}
-
-func SaveSkill(name, old, content string) error {
-	if old != "" && old != name {
-		if od, err := safeSkillDir(old); err == nil {
-			_ = os.RemoveAll(od)
-		}
-	}
-	d, err := safeSkillDir(name)
-	if err != nil {
-		return err
-	}
-	if err := os.MkdirAll(d, 0o755); err != nil {
-		return err
-	}
-	return os.WriteFile(filepath.Join(d, "SKILL.md"), []byte(content), 0o644)
-}
-
-// AppendSkill ajoute du contenu à la fin de SKILL.md (le crée si absent).
-// C'est le mode "offset" : l'IA peut consigner une solution trouvée sans
-// réécrire tout le skill.
-func AppendSkill(name, content string) error {
-	d, err := safeSkillDir(name)
-	if err != nil {
-		return err
-	}
-	if err := os.MkdirAll(d, 0o755); err != nil {
-		return err
-	}
-	p := filepath.Join(d, "SKILL.md")
-	existing, _ := os.ReadFile(p)
-	var b strings.Builder
-	if len(existing) > 0 {
-		b.Write(existing)
-		if !strings.HasSuffix(string(existing), "\n") {
-			b.WriteString("\n")
-		}
-		b.WriteString("\n")
-	}
-	b.WriteString(strings.TrimRight(content, "\n"))
-	b.WriteString("\n")
-	return os.WriteFile(p, []byte(b.String()), 0o644)
-}
-
-func DeleteSkill(name string) error {
-	d, err := safeSkillDir(name)
-	if err != nil {
-		return err
-	}
-	if _, err := os.Stat(d); err != nil {
-		return fmt.Errorf("introuvable")
-	}
-	return os.RemoveAll(d)
-}
-
-// skillsSystemPrompt returns the lightweight skills directory message to
-// prepend to the conversation when skills are enabled.
-func skillsSystemPrompt(caps Caps) string {
-	if !caps.Agent {
-		return ""
-	}
-	list := ListSkills()
-	var b strings.Builder
-	b.WriteString("Skill tips: the first content line is a short title (#) used as the description. Only use read when the question concerns a skill listed below — otherwise don't call the tool.\n")
-	if len(list) == 0 {
-		b.WriteString("Skills: none yet.")
-		return b.String()
-	}
-	b.WriteString("Skills:\n")
-	for _, s := range list {
-		fmt.Fprintf(&b, "- %s: %s\n", s.Name, s.Desc)
-	}
-	return strings.TrimRight(b.String(), "\n")
-}

web.go

@@ -98,9 +98,6 @@ func newWebMux() *http.ServeMux {
 	api("/api/tools/toggle", handleAgentToggle)
 	api("/api/skills", handleAgent)
 	api("/api/skills/toggle", handleAgentToggle)
-	api("/api/skill", handleSkill)
-	api("/api/skill/save", handleSkillSave)
-	api("/api/skill/delete", handleSkillDelete)
 	api("/api/mem", handleMem)
 	api("/api/mem/save", handleMemSave)
 	api("/api/mem/delete", handleMemDelete)
@@ -631,49 +628,9 @@ func handleInternet(w http.ResponseWriter, r *http.Request) {
 	})
 }
 
-func handleSkill(w http.ResponseWriter, r *http.Request) {
-	name := strings.TrimSpace(r.URL.Query().Get("name"))
-	if name == "" {
-		sendJSON(w, 200, map[string]any{"name": "", "content": "# nouveau skill\n\nDécris ici quand et comment l'IA doit utiliser ce skill.\n"})
-		return
-	}
-	c := SkillContent(name)
-	if c == "" {
-		sendJSON(w, 404, map[string]any{"error": "not found"})
-		return
-	}
-	sendJSON(w, 200, map[string]any{"name": name, "content": c})
-}
-
-func handleSkillSave(w http.ResponseWriter, r *http.Request) {
-	var req saveReq
-	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
-		sendJSON(w, 400, map[string]any{"ok": false, "error": err.Error()})
-		return
-	}
-	if err := SaveSkill(req.Name, req.Old, req.Content); err != nil {
-		sendJSON(w, 400, map[string]any{"ok": false, "error": err.Error()})
-		return
-	}
-	sendJSON(w, 200, map[string]any{"ok": true, "name": req.Name})
-}
-
-func handleSkillDelete(w http.ResponseWriter, r *http.Request) {
-	var req saveReq
-	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
-		sendJSON(w, 400, map[string]any{"ok": false, "error": err.Error()})
-		return
-	}
-	if err := DeleteSkill(req.Name); err != nil {
-		sendJSON(w, 400, map[string]any{"ok": false, "error": err.Error()})
-		return
-	}
-	sendJSON(w, 200, map[string]any{"ok": true})
-}
-
 // handleMem / handleMemSave / handleMemDelete : éditeur web des pages mémoire
-// (MEMORY/<nom>.md). Mêmes payloads que l'éditeur de skills (name/old/content)
-// pour réutiliser l'UI ; "name" = nom de fichier de la page.
+// (MEMORY/<nom>.md). Payload partagé saveReq (name/old/content) ; "name" = nom
+// de fichier de la page.
 func handleMem(w http.ResponseWriter, r *http.Request) {
 	name := strings.TrimSpace(r.URL.Query().Get("name"))
 	if name == "" {