Tighten Undertow Run's early attack pacing

docs/hd-backlog.md

@@ -6,7 +6,7 @@ Artwork coverage is unchanged at **5,463 frames in 3,625 complete sequences**, i
 
 Focused production checks passed 113 Rust tests and 186 Python tests; 5 existing Rust tests were ignored. Full validation accepts all 5,463 frames with zero rejects, plus 45 mods with one override. Three 1920×1080 SDL controls completed successfully, and Root viewed all three full images. Their PNG, RGB and alpha results matched the SourceE H5463 controls across 6,220,800 pixels, with zero measured changes. These unchanged-art controls do not establish coverage or artwork approval for lists above 128 cells, every optional policy or all placements. The latest closed native Windows result is exact SourceE H5426 at 3f3107d6: 394 passed, 26 ignored and zero failed; no native Windows SourceF execution is claimed.
 
-Original details remain Original rather than generated HD. The longer-list allowance does not repair geometry or material faults, reverse held artwork or establish every placement. Iron Coast's current 45-package resources and Mission 2 version 1.0.2 are unchanged. Exact production and historical authorities are in [runtime release evidence](hd-runtime-release.json). Validated package checkpoint; Git history records publication.
+Original details remain Original rather than generated HD. The longer-list allowance does not repair geometry or material faults, reverse held artwork or establish every placement. At this runtime activation, Iron Coast's 45 packages included Mission 2 version 1.0.2. Subsequent campaign changes are tracked in [Iron Coast retune evidence](iron-coast-retune.md). Exact production and historical authorities are in [runtime release evidence](hd-runtime-release.json). Validated package checkpoint; Git history records publication.
 
 Preserved 17 October 2026 Source-update checkpoint at 5,384 (historical coverage): Current Source C+D runtime — 17 October 2026, published `a073f73f`: HD coverage remains **5,384 frames / 3,551 sequences**, with **369 originals remaining** (260 Terrain, 75 enemies/ground objects, 33 UI/other, one boss). Both executables are rebuilt; 90 Rust / 78 Python tests, HD validation and three exact 1080p regression controls pass. Five old Rust checks remain ignored. Source C+D native Windows CI is pending; the prior `58723547` result (361 passed / 26 ignored / zero failed) is a different epoch. Earlier material, context and QA records below remain historical; this source update adds no art approval.