Cut v0.75.4 — pi 0.75.3 -> 0.75.4

One upstream patch release. PI_VERSION=latest in Dockerfile resolves
to 0.75.4 at build time, so no Dockerfile change is needed; just a
CHANGELOG promote.

Tagged speculatively before opencode-devbox v1.15.6's omos-with-pi
smoke completes — pi 0.75.4 is a single patch on top of 0.75.3, low
risk on its own. If opencode-devbox v1.15.6 surfaces a pi 0.75.4
problem in the omos-with-pi smoke (3700 MB threshold trip, etc.),
both releases would fail in symmetric ways and recovery would be a
v0.75.4b/v1.15.6b pair. Same recovery muscle as v1.15.4 -> v1.15.4b
last week.

Built on opencode-devbox:base-latest, cache-hit on base-35ee5fe7861a
since v1.14.50b — base unchanged across both bumps.

CHANGELOG.md

@@ -8,6 +8,14 @@ Tags follow the pi npm version: `v{pi_version}[letter]` — bare tag for the fir
 
 ## Unreleased
 
+## v0.75.4 — 2026-05-21
+
+pi `0.75.3` → `0.75.4` bump (one upstream patch release). Plus the AGENTS.md documentation-drift sweep clause that landed on `main` between v0.75.3 and now.
+
+- **Bump:** pi `@earendil-works/pi-coding-agent@0.75.4` baked at `/usr/bin/pi` (via `PI_VERSION=latest` resolving to 0.75.4 at build time — no Dockerfile change needed).
+- **AGENTS.md:** documentation drift sweep as explicit pre-commit workflow step (commit `ae6253a`). Companion clause added across the wider repo set the same day.
+- No image-side changes beyond the pi npm version. Built on `joakimp/opencode-devbox:base-latest` which itself is unchanged (cache-hit on `base-35ee5fe7861a` since v1.14.50b).
+
 ## v0.75.3 — 2026-05-18
 
 pi `0.74.0` → `0.75.3` bump (one upstream minor + three patch releases since the initial pi-devbox release on 2026-05-14).