CrazyPhone

Bump mod_version to 1.3.1-beta.1, fix two Fabric 26.1 sneak-presenting bugs

Fixes

• Third-person sneak-presenting silently never worked on Fabric 26.1: AvatarPresentPoseMixin (computes isPresenting/isDualPresenting for a real player via AvatarRenderer's own overridden extractRenderState) was neoforge-only, copied from an assumption that presenting never needed Fabric parity - it does, and without it presentingThisRender stayed permanently false there, so the held photo rendered at normal item size with plain vanilla sneak arms instead of the scaled, properly-posed card. Widened to both loaders.
• Dual-photo presenting (one photo in each hand) stacked both cards on top of each other on Fabric 26.1 instead of splitting them one per hand: PlayerModelPresentPoseMixin, the only place isDualPresentingThisRender gets set on >=26, was also neoforge-only and missing entirely from build.fabric26.gradle.kts. Widened and registered.

Release channel

• versionType (Modrinth) and releaseType (CurseForge) were hardcoded to "release" in all three build scripts - now read from a RELEASE_TYPE env var (defaulting to "release"), which release.yml derives from the pushed tag's own "-beta"/"-alpha" suffix, matching this project's existing tag convention (see the v1.2.0-beta.1 tag in its own history) instead of needing a separate manual toggle.