Incoming MODE processing is split into a parsing step and an execution
step, instead of a mode's effector function being involved in its own
parsing. Modes can no longer use custom logic to control their parsing,
and instead supply a combination of CHM_* flags to the parser. As a
result, we know before we try to effect any mode changes what all of
them will be.
The reauthorize hack for override is no longer necessary. A side effect
of its introduction was that `MODE #foo b x!y@z` no longer worked; in
removing it we restore that behaviour.
We gain the ability to reject various invalid inputs that:
- mutate or query unknown modes
- supply excess mode arguments
- query modes that can't be queried
In each case, whether we *should* reject it is an open question; for now
I'm rejecting the first one.
Previously, anyone on the WEBIRC gateway would get its ident if it
advertised one, which seems wrong to me.
This allows ident to be used with WEBIRC while still letting users send
their own ~username in band.
The algorithm we're using gets stuck if it has a ? and can only see a *
to feed to it, even if it could skip over that * and consume a character
following it. Remedy this by rearranging the input so * always precedes
? in runs of wildcards, so when we're matching ? we know we can skip
things.
Every other use of RPL_STATSDEBUG follows the format: <letter> :<text>
This case appeared to slip through because it's two-word argument is encoded
in a single `->data` buffer.
