v6.11.1 - the Rbx API mods actually use, finally documented

Stable documentation release. It also carries 6.11.0, which was committed but never tagged or released.

The problem this fixes

The documentation taught the classic coreai_world_spawn / _change / _set_color / _destroy
build API as the way for a Lua mod to create world objects — but the default composition
(CoreAiModsInstaller) sets RegisterWorldEditBuildBindings = false, so every one of those calls is
a stub that raises LuaApiWithheldException. Meanwhile the API a mod actually uses — the
Roblox-style Instance.new surface — was documented nowhere at all.

Added

• CoreAI/Docs/RBX_API.md — the missing reference: Instance.new and the supported classes,
  the datatype and service globals actually registered by LuaCsRbxApiBindings, the Part property
  set, a complete working mod, the four bundled sample mods (and the fact that the three playable
  ones ship active: false, enabled from the Hub → Mods tab), and the verified IL2CPP/WebGL
  stripping story. Linked from both documentation indexes.
• KNOWN_ISSUES.md — four real defects that were unrecorded:
  • the FullAccess demo's Start Tetris and the LuaMods demo's wave_started both throw,
    because their Lua is still written against the withheld build API (the bundled sample_tetris3d
    mod is the working equivalent);
  • LLMUnity throws ArgumentException: Unknown platform Unix on WebGL startup;
  • the legacy log-settings migration widens to GameLogFeature.AllBuiltIn, which excludes
    CustomA — so an upgraded project silently stops showing Lua mod errors;
  • Windows IL2CPP needs the MSVC C++ workload plus Windows SDK 10.0.19041+.
• WEBGL_BUILD_TROUBLESHOOTING.md — CS0103: WebGLInput does not exist: WebGLModule.dll is
  added to the reference set only when the active build target is already WebGL, so a
  #if UNITY_WEBGL guard does not save you — switch the platform first. Plus the
  "scripts are compiling" race right after a platform switch, the shipped WebGL settings
  (IL2CPP, Medium stripping, OptimizeSize, Brotli with JS fallback), and what link.xml was
  verified to preserve.

Fixed

• LUA_GAME_API.md and FIRST_MOD.md now lead with the Rbx API and scope the classic build surface
  to hosts that deliberately opt in. The read-only queries (coreai_world_exists / _pos / _find
  / _list_prefabs / _raycast) are unaffected and are marked as such. Same correction in the
  LiveMechanics, LiveMechanicsMods, LuaMods and MCP READMEs.
• RbxApi/Instances/README.md still described signals as NOT_IMPLEMENTED stubs awaiting a
  scheduler and the Unity binder as unwritten — both shipped long ago.
• DOCS_INDEX.md omitted five docs that exist on disk.
• INSTALL.md claimed Lua runs under IL2CPP/WebGL "without extra stripping protection" while the
  package ships a link.xml doing exactly that.
• SHIPPING_PLAYER_MACHINES.md now states that Windows Standalone currently ships Mono2x.

Also in this release (6.11.0, previously untagged)

• CoreAiChatPanel.TurnStreamingBubbles — the prose bubbles of the current turn, in the order
  they were opened. A turn splits into several bubbles when tool rounds run between prose, but
  OnResponseReceived handed the host the whole turn concatenated, so hosts that post-process
  bubbles had to rediscover them from the visual tree by CSS class and text matching. One shipping
  host re-rendered the whole response into the last bubble, duplicating prose and leaving the sealed
  bubble unrendered.

Verified

All six packages move in lockstep at 6.11.1. No runtime code changed in 6.11.1.

The WebGL/IL2CPP claims in these docs come from a real player build at Medium managed stripping:
the VContainer container builds, RbxWorldHost binds instances, bundled mods seed, the Lua VM runs a
16-check self-test with zero failures, and a mod-driven Instance.new spawns visible parts.