TuneC: a written tune becomes the bytes the player reads

The compiler, and the last thing the ladder was waiting for. A tune names
its instruments, writes sequences of notes and durations, and gives each
voice an order list of sequence names - which is where repetition comes
from, since a phrase played four times is written once and named four
times.

  #Tick 0d125000
  #Patch Oboe oboe.patch
  #Voice 0d0 Oboe
  #Sequence Verse
    0d64 0d4  0d67 0d4  0d72 0d8
  #Order 0d0
    Verse Verse Ending

"#" is a directive and ";" is a comment, exactly as in SplitBit assembly
and in the shell's scripts, and numbers are written the way the assembler
writes them. One rule across the machine rather than a third dialect -
and the rule earned itself immediately: the first tune I wrote said
"#Voice 0" and was refused, correctly, for a bare number.

WHAT IT REFUSES IS EVERYTHING THE PLAYER CANNOT NOTICE. The machine has
no names, so it cannot say a sequence does not exist. It has no lengths,
so it cannot say the voices will come apart four bars after the mistake.
A duration of nought is counted down to 255 and held, which sounds like a
hang rather than an error. And by the time a tune is loaded, "no starting
instrument" and "instrument nought" are the same byte - so the user's
ruling, that a voice with a part and no instrument is an error, can only
be kept here.

SoundPatch gains --blob, writing the same table as raw bytes. It stays
the only thing that reads soundThing's JSON: a second program parsing
that format is a second opinion about what a patch means, and the seam
between two opinions is where the LFO bug lived for a fortnight. Patches
are found beside the tune and then on a -I path, the way an include is.

THE TEST IS THAT TWO IMPLEMENTATIONS AGREE. maketune.py lays the fixture
out by hand and TuneC compiles a written source, and the suite checks
they match byte for byte - the discipline SplitDisk and sbfs.asm are held
to, for the same reason: either alone is only self-consistent. The
fixture predates the compiler, so this is also TuneC checked against
something written before it existed. Four more checks cover the four
refusals.

Also: the SoundPatch binary was tracked, alone among the six tools, and
.gitignore lists every other one. Untracked, and TuneC added beside it.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01E2JrLzFvuFX9fgi1LDRjrW

SplitBit Test Manual.md

@@ -37,7 +37,7 @@ Everything in between is somewhere on that line.
 make test
 ```
 
-Builds the five tools - and Voyager, where Raylib is installed - checks they compile under
+Builds the six tools - and Voyager, where Raylib is installed - checks they compile under
 strict ISO C, and runs the scripts in order. Takes a few seconds. Everything must pass; there are no expected failures at the
 level of the suite, only tests that record an expected failure of the assembler.
 
@@ -45,7 +45,7 @@ level of the suite, only tests that record an expected failure of the assembler.
 make sanitize
 ```
 
-The same suite with the five tools rebuilt under AddressSanitizer and
+The same suite with the six tools rebuilt under AddressSanitizer and
 UndefinedBehaviorSanitizer. See [The Sanitizer Run](#the-sanitizer-run).
 
 Individual scripts can be run on their own, from anywhere:
@@ -540,7 +540,7 @@ which stops the markers outliving the code they were about.
 make sanitize
 ```
 
-Rebuilds all five tools with `-fsanitize=address,undefined` and runs **the whole suite**
+Rebuilds all six tools with `-fsanitize=address,undefined` and runs **the whole suite**
 under them. What it reliably catches is invalid access: reads and writes off the end of an
 array, use after free, leaks, and arithmetic the standard does not define.
 
@@ -552,7 +552,7 @@ deliberate `calloc`. The machine's Program and Data memories are static arrays,
 sanitizers neither fill nor bound-check - which is the same fact, seen from a
 different side, as the overrun blind spot below.
 
-It runs everything because it used to not. It built all five tools sanitized and then ran
+It runs everything because it used to not. It built all six tools sanitized and then ran
 only `run.sh` and `terminal.sh`, so SplitDisk was compiled with the sanitizers and never
 exercised, and `native.sh` - which drives the assembler and the emulator harder than
 anything else here - was skipped entirely. Those are exactly where block arithmetic on disk