release: 1.8.0: Built-in operator help drawer and /help page

Built-in operator documentation in the panel: a CSS-only help drawer and Help page so Status checks and domain controls are explained without leaving the panel.
Added:
  - **Help** navigation entry and `/help` index page.
  - CSS-checkbox help drawer (no extra script): seeded topics for Status (Machine,
  - «?» entry points on Status and domain card heads open the matching drawer
Changed:
  - [guide.md](docs/guide.md) documents the boundary: in-panel help for card

Full detail: CHANGELOG.md (1.8.0).

internal/web/handlers/handlers_help.go

@@ -0,0 +1,22 @@
+package handlers
+
+import (
+	"net/http"
+
+	"github.com/mixeme/selfpost/internal/web/auth"
+)
+
+func (h *Handlers) HandleHelp(w http.ResponseWriter, r *http.Request) {
+	p, ok := h.principal(r)
+	if !ok {
+		http.Error(w, "internal error", http.StatusInternalServerError)
+		return
+	}
+	data := map[string]any{
+		"Title":    "SelfPost — help",
+		"User":     auth.CurrentUser(r),
+		"Active":   "help",
+		"IsGlobal": p.IsGlobal(),
+	}
+	h.view.Render(w, http.StatusOK, "help", data)
+}