Complete Rust API and migration documentation (#102)

README.md

@@ -1,20 +1,23 @@
 # MetaCrate
 
+The [Rust API and C# migration guide](docs/rust-api-guide.md) explains crate
+selection, ownership, async cancellation, errors, events, native prerequisites,
+and credential-safe OpenSim operation. The generated
+[documentation coverage report](api/DOCUMENTATION-COVERAGE.md) ties the public
+Rust surface back to the pinned C# type and member mappings.
+
 MetaCrate is a test-driven, clean native Rust reimplementation of
 [LibreMetaverse](https://github.com/cinderblocks/libremetaverse). LibreMetaverse
 is a behavioral and API reference only: the finished project must not load,
-host, bind to, invoke, or ship the .NET implementation. The current
-stage is a compiling structural shell: crate boundaries mirror the .NET library
-projects, public C# type names have Rust declarations, every upstream NUnit
-invocation has a traceable catalog entry, and every sample/tool project has a
-Rust binary target. Types, StructuredData, Imaging, PrimMesher, the MeshFoundry rendering adapter, and
-the main assembly's packet/message/asset/primitive wire-data, core
-runtime/networking, avatar-facing manager, world/social/service manager, RLV,
-LSL tools, Utilities, Vivox, and WebRTC slices now have complete callable,
-failure-only signatures. The independent downstream fixture compiles every
-cataloged type and member with zero exclusions, and all 1,289 NUnit invocations
-now have reviewed Rust parity cases. Production behavior implementation is the
-next stage.
+host, bind to, invoke, or ship the .NET implementation. The project is in
+release hardening: crate boundaries mirror the .NET libraries, every mapped
+public type and member has a documented native Rust destination, and every
+sample/tool project has a tested Rust binary target. Types, structured data,
+imaging, meshing/rendering, packet and message codecs, client/network runtime,
+avatar/world/social/service managers, RLV, LSL tools, utilities, Vivox, and
+WebRTC are implemented without a CLR bridge. The independent downstream
+fixture compiles every cataloged type and member with zero exclusions, and all
+1,289 upstream NUnit invocations have reviewed Rust parity cases.
 
 A case counts as translated only when an explicit Rust test body calls the
 mapped API and retains the upstream identity and body hash. The parity ledger
@@ -28,9 +31,9 @@ The authoritative compiled .NET surface is checked in as
 reviewed Rust destination in [`api/RUST-TYPES.tsv`](api/RUST-TYPES.tsv) and
 [`api/RUST-MAPPING.tsv`](api/RUST-MAPPING.tsv); [`api/README.md`](api/README.md)
 documents deterministic regeneration and validation.
-All API crates expose the same typed `Error` for fallible unimplemented members;
-infallible shims use `libremetaverse_types::unimplemented_api!` so placeholders
-cannot look like successful behavior.
+API mappings record ownership, async, error, overload, and native implementation
+decisions, and the generated rustdoc keeps those contracts attached to their
+exact C# documentation IDs.
 
 Building MetaCrate requires Rust 1.96 or newer.