add a separate compile-time DEBUG flag for the delta cache

reduce max amount of tags stored in object cache to avoid high memory usage

portable: sha1.h

gotwebd: rework gotweb_get_repo_{description,cloneurl} - use openat(2) since we've already opened the containing dir - use fstat(2) instead of multiple seeks - don't special case len == 0 ok and improvements by stsp

gotwebd: drop unused path parameter from got_get_repo_{owner,age} ok jamsek

gotwebd: simplify gotweb_render_index - drops the double loop; paginate in one go - avoid lstat + got_path_dir_is_empty for each entry: use dt_type if provided by the underlying filesystem - fixes a memleak: before `continue' we need to call gotweb_free_repo_dir ok stsp

gotwebd: use prev_disp to decide when to we've reached max_repos instead of hardcoding d_i - 2 and so expecting only "." and ".." as skipped entries, use t->prev_disp that is the number of repositories traversed until now (both skipped due to the pagination and the ones actually rendered.) ok jamsek

ignore regress/gotd/gotd.conf, it is generated by gotd's regression test suite

portable: ci: update MacOS image Cirrus CI is retiring its Intel-based MacOS VMs in favour of using M1 VMs which means a newer image.

getpwuid() returns NULL without setting errno if no user is found pointed out by millert@

zap double grp.h include spotted by Thomas

forward-declare conf_new_access_rule not all yacc implementations put the section in the same order: with OpenBSD' yacc it's fine, with GNU' bison it results in a warning about using an undeclared function conf_new_access_rule. extracted from -portable via thomas, ok stsp@

show full URL during got clone/fetch/send discussed with and ok jamsek, stsp

regress: consistently use ed -s didn't know about -s when writing those tests; saves some output redirection. ok jamsek

portable: add reference_parse to got-send-pack

rename GOTD_SOCK_FILENO to GOTD_FILENO_MSG_PIPE for clarity (it's not a socket)

cope with deleted references when reloading the tog log view ok op jamsek

sync files from diff.git 1dce05e8f99e9ab3e9229bf59e061ad0201a08e8

always cast ctype' is*() arguments to unsigned char ok stsp@

tedu Ted's copyright added to gotd.c by accident; doas-derived code is in auth.c

add a gotd auth test case for an explicitly denied group ok op@

add a gotd auth test case for explicitly denied users ok op@

add a test case for requests from users not listed in gotd.conf ok op@

fix group membership check in gotd auth ok op@

add missing RO and RW tokens; pointed out by op@