add C# UnitTabulator and Rust unit_converter

[jrdouceur]

This PR implements this proposal: QUDT Unit Conversion Library.docx

[jrdouceur]

@copilot

[Copilot]

Pull request overview

Adds a new unit conversion capability across the repo by introducing a Rust azure_iot_operations_facilities crate (with a UnitConverter + generated unit tables) and a new .NET Azure.Iot.Operations.UnitTabulator tool to generate the Rust unit metadata from QUDT Turtle resources.

Changes:

• Introduces azure_iot_operations_facilities Rust crate with get_converter API, conversion errors, and tests.
• Adds generated Rust lookup tables for UNECE ECE codes and QUDT unit conversion metadata.
• Adds a new .NET UnitTabulator project (T4-based) to read QUDT TTL resources and emit the Rust tables; wires it into codegen2/codegen.sln.

Reviewed changes

Copilot reviewed 20 out of 24 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
rust/azure_iot_operations_facilities/src/unit_converter.rs	Core Rust unit conversion API, parsing rules, and unit tests
rust/azure_iot_operations_facilities/src/unit_converter/ece_codes.rs	Generated UNECE → QUDT unit-name mapping table
rust/azure_iot_operations_facilities/src/lib.rs	Exposes unit converter module + re-exports public API
rust/azure_iot_operations_facilities/tests/unit_converter_tests.rs	Integration tests for converter and error cases
rust/azure_iot_operations_facilities/gen.sh	Helper script to run UnitTabulator and format generated Rust
rust/azure_iot_operations_facilities/Cargo.toml	New Rust crate manifest
rust/Cargo.toml	Adds the new crate to the Rust workspace members
codegen2/src/Azure.Iot.Operations.UnitTabulator/**	New .NET tool to read QUDT TTL and generate Rust ece_codes.rs + unit_infos.rs
codegen2/codegen.sln	Adds UnitTabulator project to the codegen2 solution