docs(bf-5jzdf): add verification note for profile_yaml fuzz harness structure

notes/bf-5jzdf.md

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+# Verification of profile_yaml Fuzz Harness Structure
+
+**Bead ID:** bf-5jzdf  
+**Date:** 2026-07-06  
+**Task:** Verify profile_yaml fuzz harness file structure
+
+## Summary
+
+Verified that `fuzz/fuzz_targets/profile_yaml.rs` exists and follows the proper fuzzer structure with all required components.
+
+## Acceptance Criteria Verification
+
+| Criterion | Status | Details |
+|-----------|--------|---------|
+| File exists | ✅ PASS | `fuzz/fuzz_targets/profile_yaml.rs` is present (774 bytes) |
+| `#![no_main]` attribute | ✅ PASS | Line 11 contains `#![no_main]` |
+| Uses `libfuzzer_sys::fuzz_target!` | ✅ PASS | Line 12 imports `libfuzzer_sys::fuzz_target` |
+| Proper UTF-8 handling | ✅ PASS | Lines 16-19: `std::str::from_utf8(data)` with early return on `Err` |
+| Calls `load_profile_yaml` | ✅ PASS | Line 22: `pdftract_core::profiles::loader::load_profile_yaml(yaml_content)` |
+| No syntax errors | ✅ PASS | File compiles cleanly, follows same pattern as other fuzz targets |
+
+## Comparison with Other Fuzz Targets
+
+Verified against `cmap_parser.rs` to confirm structural consistency:
+- Both use `#![no_main]` 
+- Both import `libfuzzer_sys::fuzz_target`
+- Both use `fuzz_target!(|data: &[u8]| { ... });` macro
+- Both have proper documentation comments
+
+## Code Review
+
+The fuzz target correctly implements INV-8 (no panic at public boundary) for the profile YAML loader:
+- Converts input bytes to UTF-8 string with early return on invalid UTF-8
+- Calls `load_profile_yaml` and discards the result (testing only that it doesn't panic)
+- Has clear documentation explaining what invariant it tests
+
+## Conclusion
+
+**Result:** All acceptance criteria PASS. The profile_yaml fuzz harness file structure is correct and ready for use.
+
+**Status:** ✅ COMPLETE - No changes needed, file structure is correct.