mod: Ext 13 — SLA sweep over pending lifecycle cases, 307/307

Composes lifecycle (Phase 3) with time (Ext 12): a timed-case pairs a case with
its state-entry tick; mod/overdue? flags pending cases (open/triaged/appealed)
past a deadline; mod/sla-sweep returns the breached report ids. Terminal states
never breach. Pure overlay — lifecycle stays timeless, caller stamps entry. +15 tests.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

lib/mod/tests/sla.sx

@@ -0,0 +1,108 @@
+;; lib/mod/tests/sla.sx — Ext 13: SLA sweep over pending lifecycle cases.
+
+(define mod-sla-count 0)
+(define mod-sla-pass 0)
+(define mod-sla-fail 0)
+(define mod-sla-failures (list))
+
+(define
+  mod-sla-test!
+  (fn
+    (name got expected)
+    (begin
+      (set! mod-sla-count (+ mod-sla-count 1))
+      (if
+        (= got expected)
+        (set! mod-sla-pass (+ mod-sla-pass 1))
+        (begin
+          (set! mod-sla-fail (+ mod-sla-fail 1))
+          (append!
+            mod-sla-failures
+            (str name "\n    expected: " expected "\n    got:      " got)))))))
+
+;; ── pending-state? ──
+
+(mod-sla-test! "open is pending" (mod/pending-state? "open") true)
+(mod-sla-test! "triaged is pending" (mod/pending-state? "triaged") true)
+(mod-sla-test! "appealed is pending" (mod/pending-state? "appealed") true)
+(mod-sla-test! "decided is not pending" (mod/pending-state? "decided") false)
+(mod-sla-test! "final is not pending" (mod/pending-state? "final") false)
+
+;; build cases in known states
+(define mod-sla-spam (mod/mk-report "r1" "u" "bob" "this is spam"))
+(define mod-sla-spam-reports (list mod-sla-spam))
+(define
+  mod-sla-triaged
+  (mod/case-triage
+    (mod/mk-case mod-sla-spam)
+    mod-sla-spam-reports
+    mod/default-rules))
+(define mod-sla-decided (mod/case-resolve mod-sla-triaged))
+(define mod-sla-open (mod/mk-case (mod/mk-report "r2" "u" "eve" "hello")))
+
+;; ── overdue? ──
+
+(define mod-sla-tc-old (mod/mk-timed-case mod-sla-triaged 0))
+(define mod-sla-tc-fresh (mod/mk-timed-case mod-sla-triaged 90))
+(define mod-sla-tc-done (mod/mk-timed-case mod-sla-decided 0))
+
+(mod-sla-test!
+  "old triaged case is overdue"
+  (mod/overdue? mod-sla-tc-old 100 50)
+  true)
+(mod-sla-test!
+  "fresh triaged case not overdue"
+  (mod/overdue? mod-sla-tc-fresh 100 50)
+  false)
+(mod-sla-test!
+  "decided case never overdue"
+  (mod/overdue? mod-sla-tc-done 100 50)
+  false)
+(mod-sla-test!
+  "age computes elapsed ticks"
+  (mod/age mod-sla-tc-old 100)
+  100)
+(mod-sla-test!
+  "boundary: exactly at deadline not overdue"
+  (mod/overdue?
+    (mod/mk-timed-case mod-sla-triaged 50)
+    100
+    50)
+  false)
+(mod-sla-test!
+  "boundary: one past deadline overdue"
+  (mod/overdue?
+    (mod/mk-timed-case mod-sla-triaged 49)
+    100
+    50)
+  true)
+
+;; ── sweep over a mixed queue ──
+
+(define
+  mod-sla-queue
+  (list
+    (mod/mk-timed-case mod-sla-triaged 0)
+    (mod/mk-timed-case mod-sla-decided 0)
+    (mod/mk-timed-case mod-sla-open 90)))      ;; r2, pending, age 10 → not
+
+(mod-sla-test!
+  "sweep finds only the overdue pending case"
+  (mod/sla-sweep mod-sla-queue 100 50)
+  (list "r1"))
+(mod-sla-test!
+  "overdue-count agrees"
+  (mod/overdue-count mod-sla-queue 100 50)
+  1)
+
+;; tighten deadline so the young open case also breaches
+(mod-sla-test!
+  "tighter deadline catches the open case too"
+  (mod/overdue-count mod-sla-queue 100 5)
+  2)
+(mod-sla-test!
+  "empty queue → no breaches"
+  (mod/sla-sweep (list) 100 50)
+  (list))
+
+(define mod-sla-tests-run! (fn () {:failures mod-sla-failures :total mod-sla-count :passed mod-sla-pass :failed mod-sla-fail}))