同步完整源码至远程：扁平化重构现状 + 未入库源文件

- 补入库：server/internal/db/dump.go、redis 分页/扫描预算测试、opsxdb-mcp main_test、
  packages/opsxdb-mcp package-lock、docs 审计与对比文档等 37 个新文件
- 含结构扁平化进行中的 80 处修改与 155 处旧结构删除（server/ src/ src-tauri/ 为当前有效源）
- 构建产物（bin/target/dist）与签名私钥仍按规则排除

server/internal/db/redis_key_page_test.go

@@ -0,0 +1,83 @@
+package db
+
+import (
+	"context"
+	"testing"
+
+	"github.com/redis/go-redis/v9"
+)
+
+type pageScanner struct {
+	steps map[uint64]struct {
+		keys []string
+		next uint64
+	}
+	visited []uint64
+}
+
+func (s *pageScanner) Scan(ctx context.Context, cursor uint64, _ string, _ int64) *redis.ScanCmd {
+	s.visited = append(s.visited, cursor)
+	step := s.steps[cursor]
+	cmd := redis.NewScanCmd(ctx, nil, "scan")
+	cmd.SetVal(step.keys, step.next)
+	return cmd
+}
+
+func TestKeyPageResumesAcrossMastersWithoutDroppingBatch(t *testing.T) {
+	first := &pageScanner{steps: map[uint64]struct {
+		keys []string
+		next uint64
+	}{
+		0:  {[]string{"a", "b"}, 17},
+		17: {[]string{"c"}, 0},
+	}}
+	second := &pageScanner{steps: map[uint64]struct {
+		keys []string
+		next uint64
+	}{
+		0: {[]string{"d"}, 0},
+	}}
+	clients := []scanClient{first, second}
+	// Simulate a page already at the next cursor of the first shard.
+	keys, pos, err := scanKeyPage(context.Background(), clients, keyScanPosition{Pattern: "*", Index: 0, Cursor: 17})
+	if err != nil || len(keys) != 2 || keys[0] != "c" || keys[1] != "d" || pos.Index != 2 || pos.Cursor != 0 {
+		t.Fatalf("keys=%v pos=%+v err=%v", keys, pos, err)
+	}
+	if len(first.visited) != 1 || first.visited[0] != 17 || len(second.visited) != 1 || second.visited[0] != 0 {
+		t.Fatalf("unexpected scan positions first=%v second=%v", first.visited, second.visited)
+	}
+}
+
+func TestKeyPageStopsAtBudgetWithResumableCursor(t *testing.T) {
+	s := &pageScanner{steps: map[uint64]struct {
+		keys []string
+		next uint64
+	}{
+		0: {nil, 1}, 1: {nil, 1},
+	}}
+	keys, pos, err := scanKeyPage(context.Background(), []scanClient{s}, keyScanPosition{Pattern: "rare*"})
+	if err != nil || len(keys) != 0 || len(s.visited) != 20 || pos.Index != 0 || pos.Cursor != 1 {
+		t.Fatalf("keys=%v calls=%d pos=%+v err=%v", keys, len(s.visited), pos, err)
+	}
+}
+
+func TestKeyPageKeepsOversizedScanBatch(t *testing.T) {
+	batch := make([]string, redisKeyListCap+3)
+	for i := range batch {
+		batch[i] = "key"
+	}
+	s := &pageScanner{steps: map[uint64]struct {
+		keys []string
+		next uint64
+	}{
+		0: {batch, 9}, 9: {[]string{"last"}, 0},
+	}}
+	keys, pos, err := scanKeyPage(context.Background(), []scanClient{s}, keyScanPosition{Pattern: "*"})
+	if err != nil || len(keys) != len(batch) || pos.Cursor != 9 || pos.Index != 0 {
+		t.Fatalf("first page keys=%d pos=%+v err=%v", len(keys), pos, err)
+	}
+	nextKeys, end, err := scanKeyPage(context.Background(), []scanClient{s}, pos)
+	if err != nil || len(nextKeys) != 1 || nextKeys[0] != "last" || end.Index != 1 {
+		t.Fatalf("second page keys=%v pos=%+v err=%v", nextKeys, end, err)
+	}
+}