fix(memory): implement GetReadyWork/GetBlockedIssues + child counters

Fixes #543, #544, #545, #546 (no-db mode regressions)

Memory backend fixes:
- GetReadyWork now properly excludes issues with open blocks dependencies
- GetBlockedIssues now includes issues with status=blocked (even with 0 blockers)
- LoadFromIssues initializes hierarchical child counters from existing IDs
  so repeated --parent creates bd-xxx.1, bd-xxx.2, etc.

JSONL path discovery:
- findJSONLPath works in no-db mode when dbPath is empty
- Honors BEADS_JSONL environment variable override
- Falls back to locating .beads directory

Based on PR #547 by @joelklabo - cherry-picked core fixes.

🤖 Generated with [Claude Code](https://claude.ai/code)

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

internal/storage/memory/ready_blocked_nodb_test.go

@@ -0,0 +1,154 @@
+package memory
+
+import (
+	"context"
+	"testing"
+	"time"
+
+	"github.com/steveyegge/beads/internal/types"
+)
+
+func TestLoadFromIssues_InitializesChildCounters(t *testing.T) {
+	store := New("")
+	ctx := context.Background()
+
+	issues := []*types.Issue{
+		{ID: "bd-parent", Title: "Parent", Status: types.StatusOpen, Priority: 1, IssueType: types.TypeEpic},
+		{ID: "bd-parent.1", Title: "Child 1", Status: types.StatusOpen, Priority: 1, IssueType: types.TypeTask},
+		{ID: "bd-parent.3", Title: "Child 3", Status: types.StatusOpen, Priority: 1, IssueType: types.TypeTask},
+		{ID: "bd-parent.1.2", Title: "Nested Child 2", Status: types.StatusOpen, Priority: 1, IssueType: types.TypeTask},
+	}
+
+	if err := store.LoadFromIssues(issues); err != nil {
+		t.Fatalf("LoadFromIssues failed: %v", err)
+	}
+
+	next, err := store.GetNextChildID(ctx, "bd-parent")
+	if err != nil {
+		t.Fatalf("GetNextChildID failed: %v", err)
+	}
+	if next != "bd-parent.4" {
+		t.Fatalf("GetNextChildID = %q, want %q", next, "bd-parent.4")
+	}
+
+	nextNested, err := store.GetNextChildID(ctx, "bd-parent.1")
+	if err != nil {
+		t.Fatalf("GetNextChildID (nested) failed: %v", err)
+	}
+	if nextNested != "bd-parent.1.3" {
+		t.Fatalf("GetNextChildID (nested) = %q, want %q", nextNested, "bd-parent.1.3")
+	}
+}
+
+func TestGetReadyWork_ExcludesIssuesWithOpenBlocksDependencies(t *testing.T) {
+	store := setupTestMemory(t)
+	defer store.Close()
+
+	ctx := context.Background()
+
+	closedAt := time.Now()
+	blocker := &types.Issue{ID: "bd-1", Title: "Blocker", Status: types.StatusOpen, Priority: 1, IssueType: types.TypeTask}
+	blocked := &types.Issue{ID: "bd-2", Title: "Blocked", Status: types.StatusOpen, Priority: 1, IssueType: types.TypeTask}
+	closedBlocker := &types.Issue{ID: "bd-3", Title: "Closed blocker", Status: types.StatusClosed, Priority: 1, IssueType: types.TypeTask, ClosedAt: &closedAt}
+	unblocked := &types.Issue{ID: "bd-4", Title: "Unblocked", Status: types.StatusOpen, Priority: 1, IssueType: types.TypeTask}
+
+	for _, issue := range []*types.Issue{blocker, blocked, closedBlocker, unblocked} {
+		if err := store.CreateIssue(ctx, issue, "test"); err != nil {
+			t.Fatalf("CreateIssue failed: %v", err)
+		}
+	}
+
+	// bd-2 is blocked by an open issue
+	if err := store.AddDependency(ctx, &types.Dependency{
+		IssueID:     blocked.ID,
+		DependsOnID: blocker.ID,
+		Type:        types.DepBlocks,
+		CreatedAt:   time.Now(),
+		CreatedBy:   "test",
+	}, "test"); err != nil {
+		t.Fatalf("AddDependency failed: %v", err)
+	}
+
+	// bd-4 is "blocked" by a closed issue, which should not block ready work
+	if err := store.AddDependency(ctx, &types.Dependency{
+		IssueID:     unblocked.ID,
+		DependsOnID: closedBlocker.ID,
+		Type:        types.DepBlocks,
+		CreatedAt:   time.Now(),
+		CreatedBy:   "test",
+	}, "test"); err != nil {
+		t.Fatalf("AddDependency failed: %v", err)
+	}
+
+	ready, err := store.GetReadyWork(ctx, types.WorkFilter{})
+	if err != nil {
+		t.Fatalf("GetReadyWork failed: %v", err)
+	}
+
+	got := map[string]bool{}
+	for _, issue := range ready {
+		got[issue.ID] = true
+	}
+
+	if got[blocked.ID] {
+		t.Fatalf("GetReadyWork should not include blocked issue %s", blocked.ID)
+	}
+	if !got[unblocked.ID] {
+		t.Fatalf("GetReadyWork should include unblocked issue %s", unblocked.ID)
+	}
+}
+
+func TestGetBlockedIssues_IncludesExplicitlyBlockedStatus(t *testing.T) {
+	store := setupTestMemory(t)
+	defer store.Close()
+
+	ctx := context.Background()
+
+	explicit := &types.Issue{ID: "bd-1", Title: "Explicitly blocked", Status: types.StatusBlocked, Priority: 1, IssueType: types.TypeTask}
+	blocker := &types.Issue{ID: "bd-2", Title: "Blocker", Status: types.StatusOpen, Priority: 1, IssueType: types.TypeTask}
+	implicitlyBlocked := &types.Issue{ID: "bd-3", Title: "Implicitly blocked", Status: types.StatusOpen, Priority: 1, IssueType: types.TypeTask}
+
+	for _, issue := range []*types.Issue{explicit, blocker, implicitlyBlocked} {
+		if err := store.CreateIssue(ctx, issue, "test"); err != nil {
+			t.Fatalf("CreateIssue failed: %v", err)
+		}
+	}
+
+	if err := store.AddDependency(ctx, &types.Dependency{
+		IssueID:     implicitlyBlocked.ID,
+		DependsOnID: blocker.ID,
+		Type:        types.DepBlocks,
+		CreatedAt:   time.Now(),
+		CreatedBy:   "test",
+	}, "test"); err != nil {
+		t.Fatalf("AddDependency failed: %v", err)
+	}
+
+	blocked, err := store.GetBlockedIssues(ctx)
+	if err != nil {
+		t.Fatalf("GetBlockedIssues failed: %v", err)
+	}
+
+	var foundExplicit, foundImplicit bool
+	for _, bi := range blocked {
+		switch bi.ID {
+		case explicit.ID:
+			foundExplicit = true
+			if bi.BlockedByCount != 0 {
+				t.Fatalf("explicit blocked issue should have BlockedByCount=0, got %d", bi.BlockedByCount)
+			}
+		case implicitlyBlocked.ID:
+			foundImplicit = true
+			if bi.BlockedByCount != 1 || len(bi.BlockedBy) != 1 || bi.BlockedBy[0] != blocker.ID {
+				t.Fatalf("implicit blocked issue blockers mismatch: count=%d blockers=%v", bi.BlockedByCount, bi.BlockedBy)
+			}
+		}
+	}
+
+	if !foundExplicit {
+		t.Fatalf("expected explicit blocked issue %s", explicit.ID)
+	}
+	if !foundImplicit {
+		t.Fatalf("expected implicitly blocked issue %s", implicitlyBlocked.ID)
+	}
+}