checkpoint: bug-851 root cause + raft TLA+ conformance spec family
Investigation & fixes (failover committed-job loss):
- root-cause bug-851 on an owned 3-node cluster: chaotic failover causes
silent committed-prefix divergence (WAL hdr.term always 0; two leaders
per term; no (term,lsn) reconcile). Evidence in repro-851/ + INVESTIGATION.
- live-validated fixes 848/849/850 (recovery-on-promotion, advertise real
applied_lsn, persist-layer contiguity guard); add waldump WAL inspector.
Specs (strict raft.tla conformance — library owns the log):
- TLA-gap-analysis.md: impl vs raft/raft.tla, gaps G1-G6.
- raft-log-replication, raft-commit-safety, raft-sim-conformance: extend
src/lib/raft to own log/commit/verification via callbacks (specs generated,
cross-spec review passed).
- ha-term-safety: controller-side adapter + config marker (R1-R7); design done.
- config-upgrade-snapshot: R8 descoped here (deps entity-bearing-snapshots, bug-857).
- roadmap + buglog (851/854/857) + .wolf knowledge updated.
Rongsong Shen
20e59d0b42