docs(bf-48nk): verify all implementation gaps closed

Confirmed that all issues from genesis bead description were already
fixed in previous runs:
- src/memoryProfiler.ts exists and fully implemented (255 lines)
- FileHeatmap treemap + timelapse: 31 tests pass
- SpanDag zoom/pan: tests pass
- All 2484 tests pass (4 skipped)

The original test failures were due to better-sqlite3 native module
version mismatch, not missing implementations.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

notes/bf-48nk-verification.md

@@ -0,0 +1,61 @@
+# Bead bf-48nk Verification
+
+**Date:** 2026-05-22
+**Task:** Genesis: FABRIC implementation gap closure
+
+## Claimed Issues (from task description)
+
+1. Failing unit tests across 10 test files (89 failed / 2206 total)
+2. Missing module: src/memoryProfiler.ts
+3. Web frontend: treemap + timelapse in FileHeatmap not implemented
+4. Web frontend: SpanDag zoom/pan interaction not implemented
+
+## Current State
+
+All claimed issues have been resolved in previous beads:
+
+### 1. Test Status
+- **All 2484 tests pass** (4 skipped)
+- Test files: 68 passed
+
+### 2. memoryProfiler Module
+- File exists: `src/memoryProfiler.ts` (255 lines)
+- Fully implemented with:
+  - MemorySnapshot capture and tracking
+  - MemoryStats with trend analysis
+  - MemoryDiff from baseline
+  - V8 heap snapshot writing
+  - Periodic capture with configurable intervals
+
+### 3. FileHeatmap (Treemap + Timelapse)
+- Test file: `src/web/frontend/test/FileHeatmap.test.tsx`
+- **31 tests pass** including:
+  - Collision toggle button
+  - View mode switching (tree/treemap/timelapse)
+  - Treemap visualization
+  - Timelapse controls (play/pause, slider)
+  - Data loading and error states
+
+### 4. SpanDag (Zoom/Pan)
+- Test file: `src/web/frontend/test/SpanDag.test.tsx`
+- Tests pass including:
+  - Data loading
+  - Zoom controls
+  - Pan interaction
+  - SVG rendering
+
+## Root Cause of Original Failures
+
+Per `notes/bf-48nk-resolution.md`, the test failures were caused by:
+- Native module version mismatch for `better-sqlite3`
+- Module compiled for NODE_MODULE_VERSION 115 vs Node.js requiring 137
+- Fixed by: `npm rebuild better-sqlite3`
+
+## Conclusion
+
+The genesis bead description was based on stale information. All implementation work was completed in prior agent runs. This verification run confirmed:
+- No missing modules
+- All tests pass
+- All features implemented
+
+No source code changes required.