feat(lambda-rs): Add instanced rendering

[vmarcella]

No description provided.

[Copilot]

Pull request overview

This PR introduces instanced rendering as a first-class feature in the lambda-rs engine, enabling efficient drawing of multiple copies of shared geometry with per-instance data. The implementation maintains backward compatibility while adding new APIs for instance-rate vertex buffers.

Key changes:

• Added VertexStepMode enum and VertexBufferLayout struct to support per-instance vertex attributes
• Introduced with_instance_buffer and with_buffer_step_mode methods on RenderPipelineBuilder
• Added render-instancing-validation feature flag for validating instance ranges and buffer bindings
• Created comprehensive tutorial and specification documentation with a working instanced quads example

Reviewed changes

Copilot reviewed 12 out of 12 changed files in this pull request and generated 6 comments.

Show a summary per file

File	Description
docs/tutorials/instanced-quads.md	New tutorial demonstrating instanced rendering with a grid of colored quads
docs/tutorials/README.md	Updated index to include new instanced rendering tutorial
docs/specs/instanced-rendering.md	Detailed specification for instanced rendering architecture and API design
docs/features.md	Documentation for the new render-instancing-validation feature flag
crates/lambda-rs/src/render/vertex.rs	Added VertexStepMode enum and VertexBufferLayout struct
crates/lambda-rs/src/render/validation.rs	Added validation functions for instance ranges and buffer bindings with tests
crates/lambda-rs/src/render/pipeline.rs	Extended RenderPipelineBuilder with instance buffer support and step mode tracking
crates/lambda-rs/src/render/mod.rs	Integrated instance validation into render command processing
crates/lambda-rs/examples/instanced_quads.rs	Complete working example rendering a 10x10 grid of instanced quads
crates/lambda-rs/Cargo.toml	Added render-instancing-validation feature flag
crates/lambda-rs-platform/src/wgpu/vertex.rs	Platform-level VertexStepMode mapping to wgpu types
crates/lambda-rs-platform/src/wgpu/pipeline.rs	Updated pipeline builder to support step modes with wgpu integration

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[Copilot]

Pull request overview

Copilot reviewed 12 out of 12 changed files in this pull request and generated no new comments.

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