fix: clamp suggest-compact counter overflow, add 9 boundary tests

Counter file could contain huge values (e.g. 999999999999) that pass
Number.isFinite() but cause unbounded growth. Added range clamp to
reject values outside [1, 1000000].

New tests cover:
- Counter overflow reset (huge number, negative number)
- COMPACT_THRESHOLD zero fallback
- session-end empty sections (no tools/files omits headers)
- session-end slice boundaries (10 messages, 20 tools, 30 files)
- post-edit-console-warn 5-match limit
- post-edit-console-warn ignores console.warn/error/debug

scripts/hooks/suggest-compact.js

@@ -44,7 +44,11 @@ async function main() {
       const bytesRead = fs.readSync(fd, buf, 0, 64, 0);
       if (bytesRead > 0) {
         const parsed = parseInt(buf.toString('utf8', 0, bytesRead).trim(), 10);
-        count = Number.isFinite(parsed) ? parsed + 1 : 1;
+        // Clamp to reasonable range — corrupted files could contain huge values
+        // that pass Number.isFinite() (e.g., parseInt('9'.repeat(30)) => 1e+29)
+        count = (Number.isFinite(parsed) && parsed > 0 && parsed <= 1000000)
+          ? parsed + 1
+          : 1;
       }
       // Truncate and write new value
       fs.ftruncateSync(fd, 0);