feat(server/m7-381): admin scan-status + manual trigger endpoints

Adds GET /api/admin/scan/status and POST /api/admin/scan/run under the
existing RequireAdmin middleware block; plumbs *library.Scanner and
library.RunScanConfig through api.Mount, server.New, and main.go so the
manual trigger reuses the same RunScan orchestrator as startup scans.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

internal/api/admin_scan_test.go

@@ -0,0 +1,102 @@
+package api
+
+import (
+	"context"
+	"encoding/json"
+	"net/http"
+	"net/http/httptest"
+	"os"
+	"testing"
+
+	"github.com/go-chi/chi/v5"
+
+	"git.fabledsword.com/bvandeusen/minstrel/internal/auth"
+)
+
+func newAdminScanRouter(h *handlers) chi.Router {
+	r := chi.NewRouter()
+	r.Route("/api/admin", func(admin chi.Router) {
+		admin.Use(auth.RequireAdmin())
+		admin.Get("/scan/status", h.handleGetScanStatus)
+		admin.Post("/scan/run", h.handleTriggerScan)
+	})
+	return r
+}
+
+func TestAdminScanStatus_NoRowReturnsEmpty(t *testing.T) {
+	if os.Getenv("MINSTREL_TEST_DATABASE_URL") == "" {
+		t.Skip("MINSTREL_TEST_DATABASE_URL not set")
+	}
+	h, pool := testHandlers(t)
+	admin := seedUser(t, pool, "rootscan", "pw", true)
+	req := httptest.NewRequest(http.MethodGet, "/api/admin/scan/status", nil)
+	req = withUser(req, admin)
+	rec := httptest.NewRecorder()
+	newAdminScanRouter(h).ServeHTTP(rec, req)
+	if rec.Code != http.StatusOK {
+		t.Fatalf("status = %d, want 200; body=%s", rec.Code, rec.Body.String())
+	}
+	var resp scanStatusResp
+	if err := json.Unmarshal(rec.Body.Bytes(), &resp); err != nil {
+		t.Fatalf("decode: %v", err)
+	}
+	if resp.ID != "" || resp.InFlight {
+		t.Errorf("expected empty payload; got %+v", resp)
+	}
+}
+
+func TestAdminScanStatus_RowReturnsValues(t *testing.T) {
+	if os.Getenv("MINSTREL_TEST_DATABASE_URL") == "" {
+		t.Skip("MINSTREL_TEST_DATABASE_URL not set")
+	}
+	h, pool := testHandlers(t)
+	admin := seedUser(t, pool, "rootscan2", "pw", true)
+	if _, err := pool.Exec(context.Background(), `
+		INSERT INTO scan_runs (started_at, finished_at, library)
+		VALUES (now() - interval '1 minute', now(), '{"scanned":10,"added":2}'::jsonb)
+	`); err != nil {
+		t.Fatalf("seed scan_runs: %v", err)
+	}
+
+	req := httptest.NewRequest(http.MethodGet, "/api/admin/scan/status", nil)
+	req = withUser(req, admin)
+	rec := httptest.NewRecorder()
+	newAdminScanRouter(h).ServeHTTP(rec, req)
+	if rec.Code != http.StatusOK {
+		t.Fatalf("status = %d", rec.Code)
+	}
+	var resp scanStatusResp
+	if err := json.Unmarshal(rec.Body.Bytes(), &resp); err != nil {
+		t.Fatalf("decode: %v", err)
+	}
+	if resp.InFlight {
+		t.Error("expected InFlight=false (finished_at set)")
+	}
+	if resp.FinishedAt == nil {
+		t.Error("expected FinishedAt to be non-nil")
+	}
+	if len(resp.Library) == 0 {
+		t.Error("expected Library jsonb to be non-empty")
+	}
+}
+
+func TestAdminTriggerScan_InFlightReturns409(t *testing.T) {
+	if os.Getenv("MINSTREL_TEST_DATABASE_URL") == "" {
+		t.Skip("MINSTREL_TEST_DATABASE_URL not set")
+	}
+	h, pool := testHandlers(t)
+	admin := seedUser(t, pool, "rootscan3", "pw", true)
+	if _, err := pool.Exec(context.Background(), `
+		INSERT INTO scan_runs (started_at) VALUES (now())
+	`); err != nil {
+		t.Fatalf("seed in-flight scan: %v", err)
+	}
+
+	req := httptest.NewRequest(http.MethodPost, "/api/admin/scan/run", nil)
+	req = withUser(req, admin)
+	rec := httptest.NewRecorder()
+	newAdminScanRouter(h).ServeHTTP(rec, req)
+	if rec.Code != http.StatusConflict {
+		t.Fatalf("status = %d, want 409; body=%s", rec.Code, rec.Body.String())
+	}
+}