docs: JTS #311 in-circle design history (mesh lane session 3)

[grootstebozewolf]

Summary

• Session 3 (GREEN) of the mesh in-circle lane: design-history archive for locationtech/jts#311 (isInCircleAdapt sketch, 2018 / tests 2026-05).
• Closes the RelateNG touch cells: unconditional II separation + Euler EF-3 + CI upgrade #311 → #1094 → #1212 lineage documentation: Stage A gate, ε note (ulp(1.0) = 2^-52 vs Shewchuk 2^-53), optional JTS PR comment draft.
• Product tip remains #1212 (sessions 1–2 already on main via docs: scout open JTS PRs + #1212 in-circle differential lane #444 / docs: JTS #1094 in-circle FFI scout + corpus code review #445).

Files

Path	Role
docs/jts-311-incircle-lane-2026-08.md	Design history + gate write-up
oracle/gen_jts311_incircle_history.py	Stage A#311 + Shewchuk-ε comparator
oracle/jts311_incircle_history.txt	22-vector table
docs/jts-open-prs-scout-2026-08.md	Session 3 + supersession links
tests/Discussion839Mre/jts-311-comment.md	Optional upstream comment draft

Gate (local)

Vectors: 22
Oracle pin: POS 1.5
EXPECTED pin failures: 0
Stage A#311 CERTAIN vs oracle conflicts: 0
Stage A#311 UNCERTAIN: 7
ε-policy CERT diverge: 0 on this table
GATE: GREEN

Test plan

• python oracle/gen_jts311_incircle_history.py with WSL oracle_bin (pin POS 1.5; exit 0)
• Optional: post jts-311-comment.md on jts#311 (not required for merge)