feat: add feedback repeat-rate trend

Add current-vs-previous 7-day repeat-rate metrics to the weekly review feedback guardrail report.

Author: haasonsaas

.github/scripts/sweep-recent-review-feedback.rb

@@ -739,7 +739,41 @@ def guardrail_lifecycle_json(backlog, issue_results:, generated_at: Time.now.utc
     }
   end
 
-  def weekly_guardrail_report_markdown(backlog, lifecycle: nil, generated_at: Time.now.utc, top_limit: 5)
+  def repeat_rate_metrics(ledger, generated_at: Time.now.utc, bucket_days: 7)
+    current_start = generated_at.utc - (bucket_days * 24 * 60 * 60)
+    previous_start = generated_at.utc - (bucket_days * 2 * 24 * 60 * 60)
+    buckets = Hash.new { |hash, key| hash[key] = { "current" => 0, "previous" => 0 } }
+    Array(ledger.fetch("findings")).each do |finding|
+      merged_at = Time.parse(finding.fetch("merged_at")).utc
+      next if merged_at < previous_start || merged_at > generated_at.utc
+
+      class_key = guardrail_class(finding).fetch("key")
+      bucket = merged_at >= current_start ? "current" : "previous"
+      buckets[class_key][bucket] += 1
+    rescue ArgumentError, KeyError
+      next
+    end
+
+    buckets.map do |class_key, counts|
+      current = counts.fetch("current")
+      previous = counts.fetch("previous")
+      delta = current - previous
+      change_percent = if previous.zero?
+        current.zero? ? 0 : nil
+      else
+        ((delta.to_f / previous) * 100).round
+      end
+      {
+        "class_key" => class_key,
+        "current_count" => current,
+        "previous_count" => previous,
+        "delta" => delta,
+        "change_percent" => change_percent
+      }
+    end.sort_by { |entry| [-entry.fetch("current_count"), -entry.fetch("previous_count"), entry.fetch("class_key")] }
+  end
+
+  def weekly_guardrail_report_markdown(backlog, lifecycle: nil, ledger: nil, generated_at: Time.now.utc, top_limit: 5)
     classes = backlog.fetch("classes")
     repo_counts = classes.each_with_object(Hash.new(0)) do |entry, counts|
       entry.fetch("repos").each do |repo|
@@ -749,6 +783,7 @@ def weekly_guardrail_report_markdown(backlog, lifecycle: nil, generated_at: Time
       end
     end.sort_by { |repo, count| [-count, repo] }
     prevented = Array(lifecycle&.fetch("issues", nil)).select { |issue| issue["action"] == "already_closed" }
+    repeat_rates = ledger ? repeat_rate_metrics(ledger, generated_at: generated_at) : []
     active = classes.first(top_limit)
 
     lines = [
@@ -795,6 +830,24 @@ def weekly_guardrail_report_markdown(backlog, lifecycle: nil, generated_at: Time
       lines << "| #{repo} | #{count} |"
     end
 
+    lines.concat(
+      [
+        "",
+        "## Repeat-rate trend",
+        "",
+        "| Class | Current 7d | Previous 7d | Delta | Change |",
+        "| --- | ---: | ---: | ---: | ---: |"
+      ]
+    )
+    if repeat_rates.empty?
+      lines << "| _No dated findings in the last two 7-day buckets_ | 0 | 0 | 0 | 0% |"
+    else
+      repeat_rates.first(top_limit).each do |entry|
+        change = entry.fetch("change_percent").nil? ? "new" : "#{entry.fetch("change_percent")}%"
+        lines << "| `#{entry.fetch("class_key")}` | #{entry.fetch("current_count")} | #{entry.fetch("previous_count")} | #{entry.fetch("delta")} | #{change} |"
+      end
+    end
+
     lines.concat(
       [
         "",
@@ -948,7 +1001,7 @@ def upsert_issue(repo:, title:, body:)
   end
 
   if options[:weekly_report_issue_repo] && !options.fetch(:dry_run)
-    report_body = EvalOpsReviewFeedbackSweep.weekly_guardrail_report_markdown(backlog || EvalOpsReviewFeedbackSweep.guardrail_backlog_json(ledger), lifecycle: lifecycle)
+    report_body = EvalOpsReviewFeedbackSweep.weekly_guardrail_report_markdown(backlog || EvalOpsReviewFeedbackSweep.guardrail_backlog_json(ledger), lifecycle: lifecycle, ledger: ledger)
     EvalOpsReviewFeedbackSweep.upsert_issue(
       repo: options.fetch(:weekly_report_issue_repo),
       title: options.fetch(:weekly_report_issue_title),

test/sweep_recent_review_feedback_test.rb

@@ -417,21 +417,99 @@ def test_weekly_guardrail_report_markdown_summarizes_candidates_and_prevented_cl
         }
       ]
     }
+    ledger = {
+      "findings" => [
+        {
+          "repo" => "evalops/platform",
+          "pr_title" => "proto: regenerate SDKs",
+          "path" => "proto/codex/v1/codex.proto",
+          "body_first_line" => "generated TypeScript SDK is stale",
+          "feedback_class" => "review_thread",
+          "kind" => "review_thread",
+          "merged_at" => "2026-05-09T06:00:00Z"
+        },
+        {
+          "repo" => "evalops/proto",
+          "pr_title" => "buf: add meter event",
+          "path" => "gen/go/meter/v1/event.pb.go",
+          "body_first_line" => "generated Go output was not committed",
+          "feedback_class" => "review_thread",
+          "kind" => "review_thread",
+          "merged_at" => "2026-05-01T06:00:00Z"
+        },
+        {
+          "repo" => "evalops/deploy",
+          "pr_title" => "fix: harden parser",
+          "path" => nil,
+          "body_first_line" => "Parse real CLI flags instead of substring matching",
+          "feedback_class" => "top_level_pr_comment",
+          "kind" => "pr_comment",
+          "merged_at" => "2026-05-08T06:00:00Z"
+        }
+      ]
+    }
 
     report = EvalOpsReviewFeedbackSweep.weekly_guardrail_report_markdown(
       backlog,
       lifecycle: lifecycle,
+      ledger: ledger,
       generated_at: Time.utc(2026, 5, 10, 6, 15, 0)
     )
 
     assert_includes report, "# Weekly review feedback guardrail report"
     assert_includes report, "<!-- evalops-review-feedback-weekly-report -->"
     assert_includes report, "| 1 | `generated-contract-drift` Generated contract drift | 140 | 2 | evalops/platform, evalops/proto |"
     assert_includes report, "| evalops/platform | 1 |"
+    assert_includes report, "## Repeat-rate trend"
+    assert_includes report, "| `parser-cli-contract` | 1 | 0 | 1 | new |"
+    assert_includes report, "| `generated-contract-drift` | 1 | 1 | 0 | 0% |"
     assert_includes report, "`parser-cli-contract` https://github.com/evalops/.github/issues/50"
     assert_includes report, "`generated-contract-drift`: Add generated-output drift checks."
   end
 
+  def test_repeat_rate_metrics_buckets_findings_by_merged_at
+    ledger = {
+      "findings" => [
+        {
+          "repo" => "evalops/deploy",
+          "pr_title" => "fix parser",
+          "body_first_line" => "Parse CLI flags",
+          "feedback_class" => "top_level_pr_comment",
+          "kind" => "pr_comment",
+          "merged_at" => "2026-05-09T00:00:00Z"
+        },
+        {
+          "repo" => "evalops/deploy",
+          "pr_title" => "fix parser",
+          "body_first_line" => "Parse CLI args",
+          "feedback_class" => "top_level_pr_comment",
+          "kind" => "pr_comment",
+          "merged_at" => "2026-05-02T00:00:00Z"
+        },
+        {
+          "repo" => "evalops/deploy",
+          "pr_title" => "old parser",
+          "body_first_line" => "Parse CLI command",
+          "feedback_class" => "top_level_pr_comment",
+          "kind" => "pr_comment",
+          "merged_at" => "2026-04-20T00:00:00Z"
+        }
+      ]
+    }
+
+    metrics = EvalOpsReviewFeedbackSweep.repeat_rate_metrics(
+      ledger,
+      generated_at: Time.utc(2026, 5, 10, 0, 0, 0)
+    )
+
+    assert_equal 1, metrics.length
+    assert_equal "parser-cli-contract", metrics.first.fetch("class_key")
+    assert_equal 1, metrics.first.fetch("current_count")
+    assert_equal 1, metrics.first.fetch("previous_count")
+    assert_equal 0, metrics.first.fetch("delta")
+    assert_equal 0, metrics.first.fetch("change_percent")
+  end
+
   def test_weekly_guardrail_report_markdown_handles_empty_backlog
     backlog = {
       "schema_version" => "evalops.review_feedback_guardrail_backlog.v1",