Implement binary SAVE/LOAD, INKEY$ extended keys, golden tests, update to v0.10.0

Binary SAVE/LOAD: SAVE now writes tokenized binary by default (0xFF header
format), matching original GW-BASIC behavior. SAVE "file",A for ASCII.
LOAD auto-detects binary vs ASCII from the first byte. Command-line file
loading also auto-detects, so binary .BAS files just work.

INKEY$ extended keys: arrow keys, Home/End/PgUp/PgDn, Insert/Delete, and
F1-F10 now return the correct CHR$(0) + scan_code two-byte sequences per
the IBM PC convention. Refactored event trap key parsing to use tui_read_key()
instead of duplicating escape sequence parsing.

Golden-file regression tests: generated .expected output files for 55 of 58
test programs (3 timing-dependent tests excluded). The test runner now
reports compat match status alongside pass/fail.

Classic programs: added Hamurabi, Lunar Lander, Gunner, and Diamond from
David Ahl's BASIC Computer Games (1978) in tests/classic/ for manual
compatibility testing.

Docs updated with compiler roadmap item and hardware I/O simulator plan.

tests/expected/mult_table.expected

@@ -0,0 +1,15 @@
+  X   1   2   3   4   5   6   7   8   9  10  11  12
+---------------------------------------------------
+  1   1   2   3   4   5   6   7   8   9  10  11  12
+  2       4   6   8  10  12  14  16  18  20  22  24
+  3           9  12  15  18  21  24  27  30  33  36
+  4              16  20  24  28  32  36  40  44  48
+  5                  25  30  35  40  45  50  55  60
+  6                      36  42  48  54  60  66  72
+  7                          49  56  63  70  77  84
+  8                              64  72  80  88  96
+  9                                  81  90  99 108
+ 10                                     100 110 120
+ 11                                         121 132
+ 12                                             144
+Multiplication table OK