Release MIDI Tools 0.2.0

docs/ARCHITECTURE.md

@@ -2,6 +2,20 @@
 
 `core/midi.ts` turns a bounded SMF byte stream into inert tracks and absolute-tick events. Chunk boundaries, four-byte VLQs, running status, event counts, SysEx size, PPQN division and known fixed-length meta events are validated before data is exposed. Editing functions clone this model and preserve stable event ordering.
 
-`Workbench.tsx` keeps the last valid document during failed imports or operations. The SVG piano roll renders at most 5,000 notes. Playback maps ticks through the tempo map, creates fixed application-owned sine oscillators and can stop immediately by closing the active `AudioContext`; imported bytes never become code or remote references.
+`Workbench.tsx` keeps the last valid document during failed imports or
+operations. Parsing, transforms and exports execute through a disposable module
+worker; progress messages are revision-scoped, cancellation terminates the
+worker and late messages cannot replace newer state. A no-Worker fallback exists
+for test and older-browser resilience, while the shipped browser path stays
+off-main. The SVG piano roll renders at most 5,000 notes. Playback maps ticks
+through the tempo map, creates fixed application-owned sine oscillators and can
+stop immediately by closing the active `AudioContext`; imported bytes never
+become code or remote references.
+
+Paired notes can be selected in the SVG piano roll and edited through the same
+worker protocol as bulk transforms. Web MIDI access is requested only after an
+explicit click, without SysEx permission; scheduled output is bounded and Stop
+sends all-notes-off on every channel. The local SoundFont inspector validates
+RIFF `sfbk` structure and reports INFO/pdta counts but does not render the bank.
 
 All Vite assets use relative paths for nested portal mounting. Release packaging fixes ZIP ordering, timestamps and permissions.