feat: management API and an MCP tool per SEO admin operation

- /_seo/api/v1 routes for the effective SEO of a URL with sources and
  owner, URL rules, redirects (loops refused with redirect_loop), the
  404 log actions, robots.txt and its tester, settings and history
- the CMS-data issue report: missing and duplicate titles and
  descriptions, rules over records, redirect chains, canonicals to
  noindex or redirected addresses, noindex addresses robots.txt blocks
- 24 MCP tools on those routes (backend guard, golem15.seo.manage)
- AdminOperations maps every admin operation to its tool;
  TestEveryAdminOperationHasTool and TestMCPReadToolsAreGET guard drift
- robots.txt writes go through classes.SaveRobots from the admin too

controllers/api/history.go

@@ -0,0 +1,95 @@
+package api
+
+import (
+	"context"
+	"net/http"
+
+	"git.golem15.com/golem15/sm-seo-plugin/classes"
+	"git.golem15.com/golem15/sm-seo-plugin/models"
+)
+
+// ListHistoryInput is the query of GET /_seo/api/v1/history.
+type ListHistoryInput struct {
+	Page    int    `json:"page,omitempty" query:"page" jsonschema:"the page number, from 1"`
+	PerPage int    `json:"per_page,omitempty" query:"per_page" jsonschema:"rows per page, at most 200 (50 by default)"`
+	Search  string `json:"search,omitempty" query:"search" jsonschema:"text the description contains"`
+	Via     string `json:"via,omitempty" query:"via" jsonschema:"admin, mcp, import, auto or undo"`
+	Kind    string `json:"kind,omitempty" query:"kind" jsonschema:"entry, rule, redirect, robots, settings or notfound"`
+	Batch   string `json:"batch,omitempty" query:"batch" jsonschema:"a batch id: the changes of one batch or import"`
+}
+
+// HistoryIDInput names one history entry.
+type HistoryIDInput struct {
+	ID uint `json:"id" path:"id" jsonschema:"the history entry id"`
+}
+
+// RevisionJSON is a history entry in an answer.
+func RevisionJSON(r models.Revision) map[string]any {
+	batch := ""
+	if r.BatchID != nil {
+		batch = *r.BatchID
+	}
+	return map[string]any{
+		"id": r.ID, "created_at": r.CreatedAt, "author": r.AuthorLabel, "author_id": r.AuthorID,
+		"via": r.Via, "kind": r.SubjectKind, "subject": r.SubjectID, "what": r.What,
+		"before": r.Before, "after": r.After, "batch_id": batch, "undone_at": r.UndoneAt,
+	}
+}
+
+// ListHistory serves GET /_seo/api/v1/history: newest first, filtered by
+// writer, subject kind, batch and description text (D-13).
+func ListHistory(service func() *classes.Service) http.HandlerFunc {
+	return manage(service, func(ctx context.Context, svc *classes.Service, r *http.Request) (int, any, error) {
+		db, err := read(ctx, svc)
+		if err != nil {
+			return 0, nil, err
+		}
+		in := listParams(r)
+		q := db.Model(&models.Revision{}).Order("id DESC")
+		if in.Search != "" {
+			q = q.Where("lower(what) LIKE ?", like(in.Search))
+		}
+		query := r.URL.Query()
+		if v := query.Get("via"); v != "" {
+			q = q.Where("via = ?", v)
+		}
+		if v := query.Get("kind"); v != "" {
+			q = q.Where("subject_kind = ?", v)
+		}
+		if v := query.Get("batch"); v != "" {
+			q = q.Where("batch_id = ?", v)
+		}
+		var rows []models.Revision
+		total, err := paginate(q, in, &rows)
+		if err != nil {
+			return 0, nil, err
+		}
+		out := make([]map[string]any, 0, len(rows))
+		for _, row := range rows {
+			out = append(out, RevisionJSON(row))
+		}
+		return http.StatusOK, listBody(out, in, total), nil
+	})
+}
+
+// ShowHistory serves GET /_seo/api/v1/history/{id}.
+func ShowHistory(service func() *classes.Service) http.HandlerFunc {
+	return manage(service, func(ctx context.Context, svc *classes.Service, r *http.Request) (int, any, error) {
+		id, err := pathID(r, "id")
+		if err != nil {
+			return 0, nil, err
+		}
+		db, err := read(ctx, svc)
+		if err != nil {
+			return 0, nil, err
+		}
+		var rows []models.Revision
+		if err := db.Where("id = ?", id).Limit(1).Find(&rows).Error; err != nil {
+			return 0, nil, err
+		}
+		if len(rows) == 0 {
+			return 0, nil, classes.ErrNoRecord
+		}
+		return http.StatusOK, map[string]any{"data": RevisionJSON(rows[0])}, nil
+	})
+}