test: pin command dispatch to C's command.c switch (closes #31)

Audits every case label in C's command.c against this port's dispatch and
leaves the audit behind as a standing test, so the two lists cannot drift
again. A missing dispatch entry is the one porting error that leaves no
trace at build time: the port is function-by-function, so every C function
has a Go counterpart and a dropped key dangles nothing, fails to compile
nowhere, and simply answers "illegal command" the first time a player
presses it. That is how '+' (#11) survived until PR #30 found it by
accident.

Result: no further missing keys. '+' was the only one. Recording that as a
negative result — the class of bug is real, it has now been searched for
exhaustively rather than stumbled upon, and the search came back empty.
Eighty labels: sixty-five in the main switch, fifteen in the wizard
sub-switch.

commandHandlers is pinned by set equality in both directions. A missing key
is the '+' bug; an extra key is the same bug mirrored, since the likeliest
way to acquire one is promoting a key out of the wizard sub-switch, which
would expose a MASTER debug command in ordinary play. The main-switch keys
that commandHandlers cannot hold - the goto-over re-dispatches, F-to-f, 'a'
and 'm' - are covered separately through dispatchKey, because dropping one
of those is just as silent as dropping a map entry.

Two traps are documented in the file. rogue.h 52-53 defines when as
break;case, so a grep for 'case ' finds ten of the eighty labels. And the
main/wizard split is load-bearing: '+' was a divergence in ordinary play,
not just wizard mode, precisely because it is a main-switch key.

Confirms this port targets the MASTER build: all four #ifdef MASTER sites
in command.c are ported unconditionally, as is sticks.c 237.

TODO.md

@@ -34,6 +34,27 @@ wizard commands).
 
 # Completed Steps
 
+- 2026-08-09 Command dispatch audit (`audit/command-switch-coverage`, closes
+  #31): checked every case label in C's `command.c` against this port's
+  dispatch, and left the audit behind as a standing test
+  (`game/dispatch_test.go`) so the two cannot silently drift again. **No further
+  missing keys were found** — `'+'` (#11) was the only one. That is the result,
+  and it is worth recording as a negative: the class of bug exists, it has now
+  been searched for exhaustively rather than stumbled upon, and the search came
+  back empty. Three tables transcribe C's labels with their line numbers:
+  main-switch keys answered from `commandHandlers`, main-switch keys whose arms
+  need `dispatchKey`'s own switch (the `goto over` re-dispatches, `F`-to-`f`,
+  `a`, `m`), and the `if (wizard)` sub-switch. `commandHandlers` is pinned by
+  set equality in **both** directions: a missing key is the `'+'` bug, and an
+  extra key is the same bug mirrored — a MASTER debug command leaking into
+  ordinary play. Two traps make this audit harder than it sounds and are
+  documented in the file: `rogue.h` 52-53 defines `when` as `break;case`, so a
+  grep for `case ` finds ten of the eighty labels; and the main/wizard split is
+  load-bearing, since `'+'` was a divergence in ordinary play precisely because
+  it is a main-switch key. Confirms the port targets the MASTER build — all four
+  `#ifdef MASTER` sites in `command.c` are ported unconditionally, as is
+  `sticks.c` 237.
+
 - 2026-08-09 Three small lost C behaviors (`fix/lost-c-behaviors`, closes #13):
   grouped because each is a few lines and all are "restore something the port
   dropped silently". (1) **"what a bizarre schtick!"**, `sticks.c` 237 — the