Add fleet ops dashboard, Calibrate enforcement, and dead-code cleanup.

Ship live alerts, pool status, AI monitor, remote agent commands, build manager, and uninstall flow; wire Calibrate settings (WS ping, pool traffic log, retention limits) at runtime and exclude server/data from git.

server/internal/builder/fusion_upload_test.go

@@ -0,0 +1,57 @@
+package builder
+
+import (
+	"bytes"
+	"mime/multipart"
+	"net/textproto"
+	"os"
+	"path/filepath"
+	"testing"
+)
+
+func TestSaveUploadedPrepCreatesPrepsDir(t *testing.T) {
+	dataDir := t.TempDir()
+	h := &Handler{dataDir: dataDir}
+
+	body := &bytes.Buffer{}
+	w := multipart.NewWriter(body)
+	partHeader := make(textproto.MIMEHeader)
+	partHeader.Set("Content-Type", "application/octet-stream")
+	partHeader.Set("Content-Disposition", `form-data; name="prep_exe"; filename="prep.exe"`)
+	part, err := w.CreatePart(partHeader)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if _, err := part.Write([]byte("MZfake")); err != nil {
+		t.Fatal(err)
+	}
+	w.Close()
+
+	r := multipart.NewReader(body, w.Boundary())
+	form, err := r.ReadForm(10 << 20)
+	if err != nil {
+		t.Fatal(err)
+	}
+	fileHeaders := form.File["prep_exe"]
+	if len(fileHeaders) == 0 {
+		t.Fatal("missing file header")
+	}
+	f, err := fileHeaders[0].Open()
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer f.Close()
+
+	path, cleanup, err := h.saveUploadedPrep(f, fileHeaders[0])
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer cleanup()
+
+	if _, err := os.Stat(path); err != nil {
+		t.Fatalf("prep not saved: %v", err)
+	}
+	if _, err := os.Stat(filepath.Join(dataDir, "preps")); err != nil {
+		t.Fatalf("preps dir not created: %v", err)
+	}
+}