spectra(note-to-html): 9.3 pipeline + decoder tests — 37/37 ALL DONE

ZIP/plist coverage via synthesized .note (note-to-html-swift, 5 tests);
stroke/timeline binary decoder units (note-core-swift, 9 tests).

Author: kiki830621

openspec/changes/note-to-html/tasks.md

@@ -59,7 +59,7 @@
 
 - [x] 9.1 Update `CONVERSIONS.md` with Note → HTML row in the cross matrix
 - [x] 9.2 Update `README.md` with `macdoc convert --to html file.note` usage examples
-- [ ] 9.3 Add tests: ZIP extraction, plist parsing, stroke decoding, timeline decoding, HTML output structure
+- [x] 9.3 Add tests: ZIP extraction, plist parsing, stroke decoding, timeline decoding, HTML output structure — pipeline coverage in note-to-html-swift (5 tests: ZIP/plist via synthesized .note + HTML structure/themes) + binary decoder units in note-core-swift (9 tests: strokes/timeline)
 
 ## 10. Layer 3 Package Structure Verification