fix(mail-overview): don't re-notify the prior batch, flatten newlines

The lastmod range is inclusive at both ends and the stored revision
was reused as the next start, so the batch just notified matched
again. Start one revision later.

A subject can contain a newline, which broke the bullet rows and the
+N more count; flatten CR/LF to a space before escaping.

Also reconciles the state-write comment and spec with the actual
skip-and-advance failure behavior, and corrects two doc wordings.

1 files changed, 7 insertions, 5 deletions

diff --git a/mail-overview/mail-notify.sh b/mail-overview/mail-notify.sh
index e6c9868..b132775 100755
--- a/mail-overview/mail-notify.sh
+++ b/mail-overview/mail-notify.sh
@@ -25,7 +25,7 @@
 #
 # Usage:
 #   mail-notify.sh          watch forever (what autostart runs)
-#   mail-notify.sh --once   process one tick and exit (what the test drives)
+#   mail-notify.sh --once   process one tick and exit (for manual verification, one tick)
 
 set -u
 
@@ -104,6 +104,7 @@ build_body() {
 
     rowtext="$(printf '%s' "$json" | jq -r '
         .[] | "• " + ((.authors // "(unknown)") + " — " + (.subject // "(no subject)"))
+        | gsub("[\r\n]+"; " ")
         | gsub("&"; "&amp;") | gsub("<"; "&lt;") | gsub(">"; "&gt;")
     ' 2>/dev/null)" || return 0
     [[ -n "$rowtext" ]] || return 0
@@ -231,7 +232,7 @@ tick() {
     while IFS=$'\t' read -r key label; do
         [[ -n "$key" ]] || continue
 
-        query="$SCOPE and tag:account-$key and lastmod:$prev..$cur"
+        query="$SCOPE and tag:account-$key and lastmod:$((prev + 1))..$cur"
 
         count="$(notmuch count "$query" 2>/dev/null)"
         # Same validation, same reason: an empty string must not become a
@@ -245,9 +246,10 @@ tick() {
         notify_account "$label" "$key" "$count" "$(build_body "$rows" "$count")"
     done < <(parse_accounts < "$CONFIG")
 
-    # Written only after every account is done, so a failure part way through
-    # leaves prev unchanged and the next tick retries rather than dropping a
-    # batch silently.
+    # Written only after every account is done. A single account whose count
+    # fails to validate is skipped above but does not hold the revision back;
+    # leaving it behind would re-notify every successful account's range on
+    # each later tick. Only a failed state write itself leaves prev unchanged.
     write_state "$uuid" "$cur"
 }