fix(dotnet): expand dotnet_takes_value, and keep `/flag` from eating a value

dotnet's `-c`/`-f`/`-r`/`-a`/`-l` and their long forms all take a value;
without them the value tokenizes as a free positional and lands in the
project-path detection. `-l` is also the alias `has_trx_logger_arg` was blind
to, so `dotnet test -l trx` had RTK inject a second trx logger over the user's.

The single letters overlap MSBuild's own switches, which the Msbuild dialect
spells uniformly: `/r` is MSBuild's boolean `restore`, not dotnet's
`-r <rid>`. An MSBuild switch attaches its value with `:` (`/bl:x.binlog`) and
never consumes the next argument, so the tokenizer no longer links one for the
slash spelling -- otherwise `dotnet build /r -bl:my.binlog` hid the user's own
binlog from has_binlog_arg and RTK injected a second `-bl` on top of it.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>