feat(admin): reset a user's recommendations from the users panel

- POST /admin/users/{id}/reset-recommendations clears the taste profile
  (onboarding, CF vector, bandit), play stats and wave impressions; likes,
  dislikes and history stay, wave sessions stay so a playing wave keeps going
- moderators may reset plain users, admins anyone including themselves;
  the reset is written to the audit log
- users panel gets the menu action with a confirmation; docs updated

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

services/api/internal/auth/policy_test.go

@@ -37,16 +37,17 @@ func TestCan(t *testing.T) {
 func TestCanManageUser(t *testing.T) {
 	actions := map[UserAction]string{
 		UserCreate: "create", UserEdit: "edit", UserResetPassword: "reset", UserBlock: "block",
-		UserChangeRole: "role", UserDelete: "delete",
+		UserChangeRole: "role", UserDelete: "delete", UserResetRecommendations: "recs",
 	}
 	// want[actor][target] для каждого действия; порядок ролей — user, moderator, admin.
 	cases := map[UserAction][3][3]bool{
-		UserCreate:        {{false, false, false}, {true, false, false}, {true, true, true}},
-		UserEdit:          {{false, false, false}, {true, false, false}, {true, true, true}},
-		UserResetPassword: {{false, false, false}, {true, false, false}, {true, true, true}},
-		UserBlock:         {{false, false, false}, {true, false, false}, {true, true, true}},
-		UserChangeRole:    {{false, false, false}, {false, false, false}, {true, true, true}},
-		UserDelete:        {{false, false, false}, {false, false, false}, {true, true, true}},
+		UserCreate:               {{false, false, false}, {true, false, false}, {true, true, true}},
+		UserEdit:                 {{false, false, false}, {true, false, false}, {true, true, true}},
+		UserResetPassword:        {{false, false, false}, {true, false, false}, {true, true, true}},
+		UserBlock:                {{false, false, false}, {true, false, false}, {true, true, true}},
+		UserChangeRole:           {{false, false, false}, {false, false, false}, {true, true, true}},
+		UserDelete:               {{false, false, false}, {false, false, false}, {true, true, true}},
+		UserResetRecommendations: {{false, false, false}, {true, false, false}, {true, true, true}},
 	}
 	roles := [3]Role{RoleUser, RoleModerator, RoleAdmin}
 	for action, want := range cases {