Upgrade Pebble Poses to V2 look directions

[Protonmatter]

Summary

• upgrade Pebble Poses from the Codex V1 8x9 PNG runtime to the V2 8x11 lossless WebP contract
• preserve the hardened standard animation rows and add a dedicated neutral frame plus 16 clockwise look directions
• add strict V2 verification, reproducible packaging, installer/runtime updates, direction QA evidence, and row previews
• document the v3.0.0 release boundary and one-pass asset provenance

Validation

• repository verifier: pass
• hatch-pet V2 atlas validator: pass with zero errors/warnings
• independent blind direction QA: cardinal pairs pass; one reviewed intermediate warning at 157.5
• independent final visual QA: pass after shared-scale normalization
• isolated rebuild: 35 generated artifacts semantically identical
• Windows Python/image/package tests: 19 pass
• Git Bash syntax: pass
• release archives: byte-reproducible across consecutive builds
• runtime ZIP contains only pet.json and spritesheet.webp

The two installer integration tests cannot be launched directly by Windows Python because the target is a Bash script; this PR's Linux validation workflow is the authoritative execution for those cases.