Add top blocking query finding to sp_HumanEventsBlockViewer

[erikdarlingdata]

Summary

• Adds check 9 ("Top Blocking Query") to the findings result set
• Extracts the blocker's sql_handle + statement offsets from the BPR execution stack, sums wait time inflicted on blocked sessions
• Deduplicates across monitor loops (MAX wait per victim transaction before summing) to avoid inflating numbers
• Reports: total wait time caused, percentage of total blocking, count of distinct blocked sessions
• 10% cutoff — only queries responsible for >= 10% of total blocking wait time are shown
• Query text in object_name is newline-stripped and truncated to 200 chars

Test plan

• Deployed to SQL2022, generated blocking with concurrent sessions, verified check 9 output
• Percentages sum correctly and align with check 1000 totals
• NULL sql_handle rows (sleeping/background blockers) excluded cleanly
• Proc compiles without errors

🤖 Generated with Claude Code