Fixed

• Composite glyph DoS hardening (#418) — added shared work budget (maxCompositeComponents=4096) and cycle-detection map to both composite recursion sites. The depth-only guard (32 levels) did not bound multiplicative fan-out. Cycle hits degrade gracefully; gvar delta application skipped for composites (wrong point-number space). Patch contributed by issue author.
• Software adapter hang (#421) — SDF GPU pipeline hung on software/CPU adapters (llvmpipe, SwiftShader, WARP). SDFAccelerator now implements AdapterAware — shapes route to CPU rasterizer on software.

Added

• Tiered GPU rendering strategy — gpuRenderStrategy enum (Full/NoMSAA/RasterAtlas) auto-detected from adapter type + MSAA support.
• CI GPU golden tests — Mesa lavapipe on Ubuntu CI. GPU/CPU dual-render comparison tests.

Changed

• Dependencies: golang.org/x/image v0.43.0 → v0.44.0, golang.org/x/text v0.39.0 → v0.40.0.