Address PR #235 review feedback

- Add note that PR pending issues should re-triage from scratch if PR gets closed
- Update Y-stream sweep to check build in buildroot using check_build_in_buildroot()
- Clarify all postponed categories trigger full re-triage when unblocked (not just push to queue)
- Acknowledge backoff is optional, fixed intervals may be simpler given unpredictability

Assisted-by: Claude Sonnet 4.5 (1M context) <noreply@anthropic.com>

Author: majamassarini

research/postponed-issues-reprocessing/index.md

@@ -59,9 +59,12 @@ Issues can change postponement reasons:
 
 ### 1. Dependency CVE Sweep
 
-**What it checks:** Whether the blocking dependency issue now has "Fixed in build" set
+**What it checks:** Whether the dependency's fixed build is present in the Y-stream buildroot
 
-**Method:** Jira API field lookup on the blocker issue
+**Method:**
+
+1. Jira API field lookup on the blocker issue to get "Fixed in build" NVR
+2. Use `check_build_in_buildroot()` (from `ymir/common/utils.py`) to verify that NVR is available in the Y-stream buildroot
 
 **Blocker identification:**