Check the reference corpus in, so the build stops needing the Go submodule

All 41 .bas/.txt pairs copied byte for byte from basicinterpreter@d76162c into
tests/reference/, plus the Commodore font into assets/fonts/ -- the two things
that tied the build to deps/basicinterpret. Both were verified cmp-identical
to the submodule copies.

This reverses a decision that was deliberate and correct at the time: the
corpus was driven in place because copying a submodule's corpus guarantees
drift. Overruled on purpose -- the Go dependency is being deprecated, and a
build that cannot run its acceptance suite without cloning the implementation
it replaced is not finished. tests/reference/README.md records what the drift
now costs and that those expectations are never edited.

Checked rather than assumed: both configurations configure, build and pass
from scratch with deps/basicinterpret moved out of the tree entirely.

The submodule is kept as the behavioural spec, which is a real use. The font
came with an open licence question; assets/fonts/PROVENANCE.md states it.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Co-Authored-By: Andrew Kesterson <andrew@aklabs.net>

tests/reference/language/functions/atn.bas

@@ -0,0 +1 @@
+10 PRINT ATN(3)

tests/reference/language/functions/atn.txt

@@ -0,0 +1 @@
+1.249046

tests/reference/language/functions/chr.bas

@@ -0,0 +1,3 @@
+10 PRINT "97 : " + CHR(97)
+20 PRINT "65 : " + CHR(65)
+30 PRINT "64 : " + CHR(64)

tests/reference/language/functions/chr.txt

@@ -0,0 +1,3 @@
+97 : a
+65 : A
+64 : @

tests/reference/language/functions/cos.bas

@@ -0,0 +1 @@
+10 PRINT COS(90)

tests/reference/language/functions/cos.txt

@@ -0,0 +1 @@
+-0.448074

tests/reference/language/functions/hex.bas

@@ -0,0 +1 @@
+10 PRINT HEX(255)

tests/reference/language/functions/hex.txt

@@ -0,0 +1 @@
+ff

tests/reference/language/functions/instr.bas

@@ -0,0 +1,3 @@
+10 X$ = "HELLO"
+20 Y$ = "LLO"
+30 PRINT INSTR(X$, Y$)

tests/reference/language/functions/instr.txt

@@ -0,0 +1 @@
+2

tests/reference/language/functions/left.bas

@@ -0,0 +1 @@
+10 PRINT LEFT("HELLO", 2)

tests/reference/language/functions/left.txt

@@ -0,0 +1 @@
+HE

tests/reference/language/functions/len.bas

@@ -0,0 +1,5 @@
+10 A$ = "HELLO"
+20 STRLEN# = LEN(A$)
+30 IF STRLEN# == 5 THEN GOTO 50
+40 PRINT "FAILURE"
+50 PRINT "SUCCESS"

tests/reference/language/functions/len.txt

@@ -0,0 +1 @@
+SUCCESS

tests/reference/language/functions/log.bas

@@ -0,0 +1 @@
+10 PRINT LOG(3.14)

tests/reference/language/functions/log.txt

@@ -0,0 +1 @@
+1.144223

tests/reference/language/functions/mid.bas

@@ -0,0 +1,3 @@
+10 A$ = "HELLO"
+20 B$ = MID(A$, 2, 3)
+30 PRINT B$

tests/reference/language/functions/mid.txt

@@ -0,0 +1 @@
+LLO

tests/reference/language/functions/mod.bas

@@ -0,0 +1,6 @@
+10 PRINT MOD(10, 3)
+20 PRINT MOD(12, 5)
+30 PRINT MOD(4, 2)
+40 REM MOD() ONLY WORKS WITH INTEGERS - RESULTS WITH FLOATING POINT ARE UNRELIABLE
+50 REM PRINT MOD(1.2, 0.4)
+60 REM THERE IS NO ERROR THROWN HERE. JUST DONT DO IT.

tests/reference/language/functions/mod.txt

@@ -0,0 +1,3 @@
+1
+2
+0

tests/reference/language/functions/pointer.bas

@@ -0,0 +1,8 @@
+10 A# = 255
+20 B# = POINTER(A#)
+30 IF PEEK(B#) == 255 THEN GOTO 50
+40 PRINT "FAILURE: PEEK != 255"
+50 POKE B#, 127
+60 IF PEEK(B#) == 127 THEN GOTO 80
+70 PRINT "FAILURE : POKE DID NOT SET 127"
+80 PRINT "SUCCESS"

tests/reference/language/functions/pointer.txt

@@ -0,0 +1 @@
+SUCCESS

tests/reference/language/functions/rad.bas

@@ -0,0 +1 @@
+10 PRINT RAD(90)

tests/reference/language/functions/rad.txt

@@ -0,0 +1 @@
+1.570796

tests/reference/language/functions/right.bas

@@ -0,0 +1,2 @@
+10 PRINT RIGHT("HELLO", 3)
+20 PRINT RIGHT("HELLO", 7)

tests/reference/language/functions/right.txt

@@ -0,0 +1,2 @@
+LLO
+HELLO

tests/reference/language/functions/sgn.bas

@@ -0,0 +1,4 @@
+10 X# = -1
+20 PRINT SGN(X#)
+30 PRINT SGN(0)
+40 PRINT SGN(1)

tests/reference/language/functions/sgn.txt

@@ -0,0 +1,3 @@
+-1
+0
+1

tests/reference/language/functions/shl.bas

@@ -0,0 +1,4 @@
+10 A# = 8
+20 B# = SHL(A#, 2)
+30 PRINT B#
+40 PRINT SHL(8, 2)

tests/reference/language/functions/shl.txt

@@ -0,0 +1,2 @@
+32
+32

tests/reference/language/functions/shr.bas

@@ -0,0 +1,4 @@
+10 A# = 32
+20 B# = SHR(A#, 2)
+30 PRINT B#
+40 PRINT SHR(32, 2)

tests/reference/language/functions/shr.txt

@@ -0,0 +1,2 @@
+8
+8

tests/reference/language/functions/sin.bas

@@ -0,0 +1 @@
+10 PRINT SIN(90)

tests/reference/language/functions/sin.txt

@@ -0,0 +1 @@
+0.893997

tests/reference/language/functions/spc.bas

@@ -0,0 +1 @@
+10 PRINT "BASIC IS" + SPC(16) + "FUN"

tests/reference/language/functions/spc.txt

@@ -0,0 +1 @@
+BASIC IS                FUN

tests/reference/language/functions/str.bas

@@ -0,0 +1,2 @@
+10 X% = -123.456
+20 PRINT STR(X%)

tests/reference/language/functions/str.txt

@@ -0,0 +1 @@
+-123.456000

tests/reference/language/functions/tan.bas

@@ -0,0 +1 @@
+10 PRINT TAN(90)

tests/reference/language/functions/tan.txt

@@ -0,0 +1 @@
+-1.995200

tests/reference/language/functions/val.bas

@@ -0,0 +1,3 @@
+10 PRINT VAL("32")
+20 PRINT VAL("123.456")
+30 PRINT VAL("-256")

tests/reference/language/functions/val.txt

@@ -0,0 +1,3 @@
+32.000000
+123.456000
+-256.000000

tests/reference/language/functions/xor.bas

@@ -0,0 +1,2 @@
+10 PRINT XOR(50, 10)
+20 PRINT XOR(25, 5)

tests/reference/language/functions/xor.txt

@@ -0,0 +1,2 @@
+56
+28