chore(buglog): log bug-1880 (sim-verify mismatch on array job dispatches) and bug-1881 (mismatch message hides the diff)

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

.wolf/bugs/bug-1881.md

@@ -0,0 +1,52 @@
+---
+id: "bug-1881"
+status: "open"
+status_updated: "2026-09-28"
+status_note: "logged 2026-09-28; fix not started"
+component: "scheduler"
+severity: "wrong-result"
+timestamp: "2026-09-28T07:26:09Z"
+last_seen: "2026-09-28T07:26:09Z"
+occurrences: 1
+files: ["src/scheduler/src/sim_verify.c"]
+tags: ["scheduler", "sim", "sim-verify", "logging"]
+related: []
+---
+
+# bug-1881: sim_log_mismatch prints identical expected/actual, hiding the field that differs
+
+## Description
+**Observed:**
+```
+... MISMATCH ... -- expected: DISPATCH jobid=0-12-1790578108-0[49] nhosts=1 -- actual: DISPATCH jobid=0-12-1790578108-0[49] nhosts=1
+```
+**Expected:** the message names the field(s) that differ, with both values.
+**Impact:** a mismatch cannot be diagnosed from the log (bug-1880: 43 such lines, none showing the difference).
+**Found by:** user reading the bug-1880 replay log, 2026-09-28
+
+## Environment
+- OS: NixOS 26.05 (Yarara); NixOS kernel; kernel Linux 6.18.33 x86_64
+- libc: glibc 2.42-47 (interpreter /nix/store/wb6rhpznjfczwlwx23zmdrrw74bayxw4-glibc-2.42-47/lib/ld-linux-x86-64.so.2)
+- Toolchain: gcc (GCC) 15.2.0, meson 1.9.1
+- Build: debug (build.dbg)
+- Code: scheduler-framework @ 4c134127 (`xce_scheduler --version`: v0.0.0.1-4c134127-85e8fc00, built 2026-09-28T06:40:21Z)
+- Deployment: pc13v: xce_scheduler in simulation mode (pid 93231) replaying a capture of the live pc13v cluster's scheduler (scheduler-replay-20260928-064842.replay, captured from 06:48:42); exact command line and --sim-start-ts not recorded
+
+## Reproduction
+1. Any --sim-verify mismatch whose decisions differ only below the jobid/nhosts level (bug-1880's replay)
+- Frequency: deterministic (43/43 lines in the pc13v run)
+- Evidence: data/xce_scheduler.log
+
+## Root cause
+sim_log_mismatch() (src/scheduler/src/sim_verify.c) summarizes each decision as kind + jobid + nhosts, while sim_decision_eq() also compares every host's allocations (resname, value, duration, reserve), so a difference there prints two identical summaries.
+
+## Fix
+TODO: required for fixed/partial
+
+## Verification
+- Test: TODO: name + file; RED before the fix, GREEN after
+- Suites: TODO: suite results and build profile
+- Live: TODO: soak/deploy run, or n/a and why
+
+## References
+- Related: bug-1880