feat(functions): tag CLASSIFICATION across functions/ and conf.d/

Audits every function's interaction with the C1-shadowed commands
(uses-shadow/bypasses-shadow) and general hazards (destructive,
network, blocking-prompt) per the CLASSIFICATION schema.

Delegated the initial mechanical sweep to agy, then reviewed every
file by hand: fixed a systemic double-blank-comment-line formatting
bug from the delegate pass, and corrected several judgment errors
found on review -- three false blocking-prompt tags where a fish
'read' was consuming piped input rather than waiting on a terminal
(open-url.fish, sbver.fish, play-media.fish, now untagged entirely),
a blocking-prompt tag on mkrep.fish despite its documented --yes
escape hatch, an untagged read in jobrunner.fish's own baseless
blocking-prompt claim (removed, along with a destructive tag on
cleanup of its own mktemp output -- the schema explicitly excludes
that), the same own-output-cleanup false positive on
_zellij_dump_log.fish's destructive tag, an interactive fzf-gated
confirmation on logs.fish and replay.fish's piped read misread the
same way as the first three, and a uses-shadow(mkdir) on mkcd.fish
that actually belongs to the _fish_mkdir_p helper it delegates to,
not to mkcd itself.

functions/mkrep.fish

@@ -9,6 +9,9 @@
 #   _mkrep_add_origin, _mkrep_default_remote_cmd, _mkrep_remote_url,
 #   _mkrep_repo_exists, git
 #
+# CLASSIFICATION
+#   uses-shadow(cd), destructive, network
+#
 # SYNOPSIS
 #   mkrep [--cd | --no-cd] [--mkdir | --no-mkdir] [--git | --no-git]
 #         [-c | --clean | --no-clean] [--strict] [-v | --verbose]