fix: keep URP 17.5 LitInput out of the DCL_Toon ForwardLit pass

[eordano]

Unity 6000.5's URP added #include "LitInput.hlsl" to LitForwardPass.hlsl, which pulls ShaderLibrary/SurfaceInput.hlsl into the one DCL translation unit that includes URP's real LitForwardPass (DCL_Toon ForwardLit) — colliding with DCL_ToonInput.hlsl (_BaseMap, Alpha, UnityPerMaterial members) and rendering avatars magenta.

Fix (+16 lines, one file): pre-claim URP's UNIVERSAL_LIT_INPUT_INCLUDED guard so the new self-include no-ops (the same guard-reuse pattern this repo already uses in Scene/URP/LitInput.hlsl), and inline the parameterless IsSurfaceTypeTransparent() that 6000.5's LitForwardPass calls — under the real file's own guard, since Shaders/Utils/SurfaceType.hlsl does not exist in 6000.4's URP. With _Surface defined 0.0f it returns false, matching the 6000.4 behavior exactly.

Cross-version verification (both zero errors, zero shader errors):

• current unity-explorer dev (Unity 6000.4.0f1) with this branch
• unity-explorer PR chore: upgrade to Unity 6000.5.4f1 unity-explorer#9392 (Unity 6000.5.4f1), including visual in-world verification (avatars correctly toon-shaded)

Safe to merge ahead of the upgrade PR; #9392 currently pins this branch and will repoint to main after merge.

🤖 Generated with Claude Code

[github-actions]

🔗 Merge Alignment Reminder

If this PR targets main, please make sure the corresponding changes in unity-explorer are also ready to merge.

Both repos should be merged in coordination to avoid breaking changes. Do not merge one without the other being ready.

[eordano]

Expanded during player-build verification

The initial commit only handled the editor-visible DCL_Toon ForwardLit collision. Running actual player builds of unity-explorer (which compile the DOTS-instancing *_INSTANCING_ON shader variants that editor compiles skip) surfaced the rest — now all fixed on this branch (head de4cce8):

• DCL_Toon.shader — pre-claim URP's UNITY_LIT_INPUT_INCLUDED guard; inline IsSurfaceTypeTransparent() (6000.4's URP has no SurfaceType.hlsl, so it's version-agnostic).
• DCL_ToonOutline/DCL_ToonHighlight — unity_ObjectToWorld → GetObjectToWorldMatrix() (not declared in DOTS variants), and added the missing UNITY_VERTEX_INPUT_INSTANCE_ID member + UNITY_TRANSFER_INSTANCE_ID so the fragment stage's UNITY_SETUP_INSTANCE_ID resolves.
• Scene/URP Lit/Unlit inputs — legacy UNITY_ACCESS_DOTS_INSTANCED_PROP_FROM_MACRO (removed in 6000.5) → UNITY_ACCESS_DOTS_INSTANCED_PROP (17 sites).
• Avatar_CelShading_DepthNormalsPass — direct unity_ObjectToWorld → GetObjectToWorldMatrix().

Cross-version player-build verified

• 6000.5.4f1 — full IL2CPP player build of unity-explorer#9392: 0 shader errors, avatars render correctly in-world.
• 6000.4.0f1 — player build of current dev + this branch: 0 shader errors (every API used — GetObjectToWorldMatrix, UNITY_ACCESS_DOTS_INSTANCED_PROP, the instance-id macros — exists in 6000.4).

Safe to merge ahead of the 6000.5 upgrade.

🤖 Generated with Claude Code

[eordano]

✅ 6000.4 clean-pass player build now confirmed: SUCCEEDED, 0 shader / 0 script errors, .app produced (the 4 counted errors are the benign pulse.transport no-meta-file warnings, identical on 6000.5). Local player-build verification is complete and green on both editors with both dependency PRs pinned. Only remaining unverified target is Windows/DirectX.

[eordano]

✅ Windows/DirectX verified. Full 6000.5.4f1 StandaloneWindows64 player build on the Windows rig succeeded — 0 shader errors, 0 CS errors across 132k log lines, Explorer.exe produced. The DCL_Toon ForwardLit, DCL/Scene, and all DOTS-instancing variants compiled clean on d3d11. This closes the last platform gap: the upgrade's shader fixes now verified on both macOS/Metal and Windows/DirectX, across both 6000.4 and 6000.5 editors.