Give sounds, instruments, patterns and songs a sound FX (#352)

A sound FX could only be picked where something was played: on a Play
node, a track or an item of a song. A sound that should always sound
through the same effect needed that pick everywhere it was used. Now
the asset says it once, and every place that plays it follows.

- New row Sound FX on a sound, an instrument, a pattern and a song,
  right before Bus. A sound goes through it on every voice, an
  instrument on every note after its graph, a pattern on all its
  notes together and a song on its output.
- The fx input of Play sound, Play note, Play pattern and Play song
  and the Sound FX of a song item now read "From the asset" while
  empty. None is a pick of its own, stored as `#none` like `#master`.
  A pick replaces the FX of the asset, it does not come on top.
- A pattern item's Instrument reads "From the asset" instead of None.
  The meaning is unchanged.
- A double-click on a sound item opens the sound, as one on a pattern
  item opens the pattern.
- The tabs play through the FX of their asset. The Pattern and Song
  tab put it on a bus of their own between the output and the bus of
  the asset. The keys of the Pattern tab play there too.
- Notes of a pattern or song go through the FX of their instrument.
  Its chain is loaded with the other needs of the sequence.

Decided without asking:
- Old items and Play nodes with an empty fx now mean "From the
  asset". No asset has an FX yet, so nothing sounds different.
- The label is "From the asset" as on Loop and Bus, not "From asset".
- A sound used as a Sample, as the impulse of a Reverb or as the test
  sound of the Sound FX tab plays without its own FX.

Findings:
- In e2e, `__gm.inspectorField('Sound FX')` and `('Instrument')` find
  the group of the Assets panel first. The check asks for the last
  match.

Tests:
- Unit asset-fx (new): 8 green. Six counter-checks each turned red.
- Field lists of sound, pattern and song: Sound FX added.
- e2e 65 (melektaus-atx): ALL PASSED, 46 checks (3 new). Counter-check
  without the FX bus of the tab: that check red.
- Gate (melektaus-atx): CHECK EXIT 0, 268 files, 4142 tests.
- Not checked: how it sounds, the Sound, Instrument and Pattern tab
  in the browser.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/core/graph/nodes/action/PlayNote.ts

@@ -10,7 +10,7 @@ export const PlayNote: NodeDef = {
   label: 'Play note',
   category: 'action',
   description:
-    'Plays one note of an instrument asset. "note" is its number as MIDI counts it: 60 is C4, 61 C#4, 72 C5. "velocity" is how hard it is struck, 0 to 1 – it makes the note quieter and is handed to what the instrument does with it. "duration" is how many seconds until the note is released; at 0 it is held until a Stop sound ends it. A note belongs to this object like a sound and stops when the object is destroyed, unless "detached" is on. "params" takes values for the parameters of the instrument from an Instrument parameters node. "fx" sends the note through a sound FX on top of what the instrument does, "fx params" takes values for its parameters from a Sound FX parameters node – the two sets stay apart. "voice" is the number of this note, for Set sound FX parameters and Stop sound; 0 where the instrument plays nothing for it. "tempo" is what a Delay in the instrument synced to beats counts by, in quarter notes a minute. "bus" is the bus it is heard on; left empty, the one the instrument names.',
+    'Plays one note of an instrument asset. "note" is its number as MIDI counts it: 60 is C4, 61 C#4, 72 C5. "velocity" is how hard it is struck, 0 to 1 – it makes the note quieter and is handed to what the instrument does with it. "duration" is how many seconds until the note is released; at 0 it is held until a Stop sound ends it. A note belongs to this object like a sound and stops when the object is destroyed, unless "detached" is on. "params" takes values for the parameters of the instrument from an Instrument parameters node. "fx" sends the note through a sound FX on top of what the instrument does; left empty, the one the instrument names, and None through none. "fx params" takes values for its parameters from a Sound FX parameters node – the two sets stay apart. "voice" is the number of this note, for Set sound FX parameters and Stop sound; 0 where the instrument plays nothing for it. "tempo" is what a Delay in the instrument synced to beats counts by, in quarter notes a minute. "bus" is the bus it is heard on; left empty, the one the instrument names.',
   inputs: [
     exec(),
     {