01 — op-1 tape undo / redo firmware

Fixes the new screens (undo popup, scale panel, FILE, sound browser, tape, sampler and effect screens) not showing, or showing at the wrong size, on some newer OP-1 displays. Features worked but had no screen, so e.g. a delete in the browser went through without its prompt. REC in tape mode no longer refuses to start on units that still have room for a take. When storage really runs low, a take started from any screen now stops with FULL instead of being lost. The release number on the boot screen is centred. Everything from #250 is included.

Adds tape edits: merge drop, copy the loop, paste at the end and bounce, one undo step each. Adds four tapes, crush, warble and plate effects, tilt sensitivity for the element LFO, sampler fit to bars, zoom and retune, and delete / rename in the sound browser. Adds a flash check, and fixes a bug in TE's firmware that slowly marked good flash as bad while using the tape. Blocks already marked bad come back only with a format (see the guide). pcppcp's op1r synths, effects and sequencers are still included.

Adds supersaw, FM bell and granular synths, tape, clouds and reverb effects (also usable as master FX), a quad LFO, and euclid and dots sequencers. Also adds MIDI CC control, a scale mode and a storage bar on the COM screen. Lift, drop, slide, split and join can now be undone, undo history survives power off, and undo works on units with nearly full tape storage. Synths, effects and sequencers come from pcppcp's op1r.

Adds an UNDO / REDO popup modelled on the OP-1 field's, and snapshot naming on a tape-reel screen (up to 12 characters).

Tape undo / redo: hold TAPE and press ← or → to step up to 7 recordings back and forward again. Punch-ins, overdubs and loop recordings undo exactly, with the tape stopped or playing.