fix(githooks): shorten commit-msg hook diagnostics

Long echo strings broke the same eighty-column rule the hook enforces on log
messages. Error output is split so the hook file itself stays readable.

- Wrap rejection messages to eighty columns or fewer
- Keep wording aligned with subject, summary, and bullet layout rules

.githooks/commit-msg

@@ -27,7 +27,7 @@ while IFS= read -r line || [[ -n "${line}" ]]; do
     if ((len > 80)); then
         echo "❌ COMMIT MESSAGE: line ${lineno} is ${len} chars (max 80)"
         echo ""
-        echo "Required layout: subject, blank, summary paragraph, blank, bullets."
+        echo "Required: subject, blank, summary, blank, then \"- ...\" bullets."
         echo "See .github/prompts/commit.prompt.md"
         echo ""
         echo "Offending line (truncated for display):"
@@ -40,7 +40,7 @@ done <"${msg_file}"
 # Drop trailing empty lines so optional final newline does not confuse counts.
 while ((${#lines[@]} > 0)); do
     last=$(( ${#lines[@]} - 1 ))
-    if [[ -z ${lines[last]} ]]; then
+    if [[ -z "${lines[last]}" ]]; then
         unset "lines[last]"
     else
         break
@@ -49,8 +49,8 @@ done
 
 n=${#lines[@]}
 if ((n < 5)); then
-    echo "❌ COMMIT MESSAGE: need subject, blank, summary, blank, then bullets"
-    echo "(at least five lines). See .github/prompts/commit.prompt.md"
+    echo "❌ COMMIT MESSAGE: need subject, blank, summary, blank, bullets"
+    echo "(five or more lines). See .github/prompts/commit.prompt.md"
     exit 1
 fi
 
@@ -81,8 +81,8 @@ if ((bullet_idx < 0)); then
 fi
 
 if ((bullet_idx < 3)); then
-    echo "❌ COMMIT MESSAGE: add at least one summary line after the subject blank"
-    echo "before the separator blank and bullets."
+    echo "❌ COMMIT MESSAGE: add a summary line after the subject blank line"
+    echo "before the blank that precedes bullets."
     exit 1
 fi
 
@@ -96,9 +96,8 @@ has_summary=0
 for ((i = 2; i < bullet_idx - 1; i++)); do
     line=${lines[i]}
     if [[ -n "${line}" ]] && [[ "${line}" =~ ^[[:space:]]*-[[:space:]] ]]; then
-        echo "❌ COMMIT MESSAGE: line $((i + 1)) looks like a bullet but is above"
-        echo "the summary block; write prose summary lines first, then a blank"
-        echo "line, then \"- ...\" bullets."
+        echo "❌ COMMIT MESSAGE: summary line $((i + 1)) starts like a bullet"
+        echo "Use prose first, one blank line, then hyphen bullets."
         exit 1
     fi
     if [[ -n "${line}" ]]; then
@@ -107,22 +106,21 @@ for ((i = 2; i < bullet_idx - 1; i++)); do
 done
 
 if ((has_summary == 0)); then
-    echo "❌ COMMIT MESSAGE: summary paragraph is empty (need 1–3 sentences before"
-    echo "the blank line that precedes bullets)."
+    echo "❌ COMMIT MESSAGE: summary paragraph is empty before the bullet list"
+    echo "Add one to three sentences, then a blank line, then bullets."
     exit 1
 fi
 
 for ((i = bullet_idx; i < n; i++)); do
     line=${lines[i]}
     if [[ -z "${line}" ]]; then
-        echo "❌ COMMIT MESSAGE: line $((i + 1)) is empty inside the bullet block;"
-        echo "remove blank lines between bullets or end the message after the last"
-        echo "bullet."
+        echo "❌ COMMIT MESSAGE: empty line $((i + 1)) inside bullet block"
+        echo "Remove blanks between bullets or end after the last bullet."
         exit 1
     fi
     if ! [[ "${line}" =~ ^[[:space:]]*-[[:space:]] ]]; then
-        echo "❌ COMMIT MESSAGE: line $((i + 1)) must be a \"- ...\" bullet after the"
-        echo "summary section."
+        echo "❌ COMMIT MESSAGE: line $((i + 1)) is not a hyphen bullet"
+        echo "Each bullet line must start with dash then space after summary."
         exit 1
     fi
 done