feat(tessellation): add screen-space adaptive tessellation and texture generator

feat(tessellation): add screen-space adaptive tessellation and texture generator

Add screen-space tessellation system that subdivides textured triangles
based on pixel edge lengths, providing per-polygon LOD that adapts to
camera distance naturally. Includes safeguards against excessive
subdivision with recursion depth limits and triangle count caps.

Add TextureGenerator factory for reusable textures with configurable
borders and glow effects (solidWithBorder, glowingBorder, radialGlow).
Textures are cached with WeakReference for automatic GC when unused.

Enhance DeveloperToolsPanel with tessellation quality controls and
real-time stats display. Propagate mouse interaction controllers
through tessellated triangles to preserve clickability.

Rewrite AGENTS.md as comprehensive quick-reference guide with
task lookup table, code examples, and class catalog organized by
package.