Add 'compile-slice' Script for Slice Compiler Definitions

[InsertCreativityHere]

This PR adds a new build/compile-slice.py script which will automatically regenerate the C# code in src/ZeroC.Slice.Symbols/Compiler based on the existing compiler definitions, and the version of slicec downloaded in the repository.

The script should be runnable anywhere from within the repository. It will automatically figure out the pathing.

I also made sure to have it forward any errors, not that there should ever be any.

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Normal output:

PS icerpc-csharp> python build/compile-slice.py
Found 'slicec' at: 'D:/Code/Workspace/icerpc-csharp\src\IceRpc.Slice.Tools\obj\tools\windows-x64\slicec.exe'
Found code-generator at: 'D:/Code/Workspace/icerpc-csharp\src\ZeroC.Slice.Generator\bin\Debug\net10.0\slicec-csharp-generator.bat'
Found output directory at: 'D:/Code/Workspace/icerpc-csharp\src\ZeroC.Slice.Symbols\Compiler'
Compiling the following files: [
    D:/Code/Workspace/icerpc-csharp\slice\Compiler\CodeGenerator.slice
    D:/Code/Workspace/icerpc-csharp\slice\Compiler\Diagnostics.slice
    D:/Code/Workspace/icerpc-csharp\slice\Compiler\DocComment.slice
    D:/Code/Workspace/icerpc-csharp\slice\Compiler\SyntaxElements.slice
]

Completed

Output if there were errors:

PS icerpc-csharp> python build/compile-slice.py
Found 'slicec' at: 'D:/Code/Workspace/icerpc-csharp\src\IceRpc.Slice.Tools\obj\tools\windows-x64\slicec.exe'
Found code-generator at: 'D:/Code/Workspace/icerpc-csharp\src\ZeroC.Slice.Generator\bin\Debug\net10.0\slicec-csharp-generator.bat'
Found output directory at: 'D:/Code/Workspace/icerpc-csharp\src\ZeroC.Slice.Symbols\Compiler'
Compiling the following files: [
    D:/Code/Workspace/icerpc-csharp\slice\Compiler\CodeGenerator.slice
    D:/Code/Workspace/icerpc-csharp\slice\Compiler\Diagnostics.slice
    D:/Code/Workspace/icerpc-csharp\slice\Compiler\DocComment.slice
    D:/Code/Workspace/icerpc-csharp\slice\Compiler\SyntaxElements.slice
]

Errors encountered while trying to compile Slice files:

error [E033]: no element with identifier 'strin' exists
  Reported by: [slicec]
 --> D:/Code/Workspace/icerpc-csharp\slice\Compiler\CodeGenerator.slice:19:11
   |
19 |     path: strin
   |           -----
   |

[Copilot]

Pull request overview

This PR introduces a new repository-local helper script to regenerate the C# sources under src/ZeroC.Slice.Symbols/Compiler from the Slice compiler definition files using the slicec binary downloaded by the build.

Changes:

• Add build/compile-slice.py to locate slicec, locate the ZeroC.Slice.Generator code generator script, and compile slice/Compiler/*.slice into src/ZeroC.Slice.Symbols/Compiler.
• Update build/sync-slice.py’s docstring usage paths to reference build/ instead of tools/.
• Remove a couple of VS Code workspace settings related to Rust Analyzer, and remove unused _SliceCExe properties from IceRpc.Slice.Tools.csproj.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 7 comments.

File	Description
src/IceRpc.Slice.Tools/IceRpc.Slice.Tools.csproj	Removes no-longer-used properties related to slicec executable naming.
build/sync-slice.py	Docstring usage text updates to match the script’s actual location under build/.
build/compile-slice.py	New script to regenerate compiler-symbol C# sources by invoking slicec + the C# generator.
.vscode/settings.json	Removes Rust Analyzer-related VS Code settings (not mentioned in PR description).

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[InsertCreativityHere]

While looking for where we store slicec, I stumbled across this.
Leftover from the old slicec-cs tool. So these are no longer doing anything for us.

[bernardnormier]

Should be slnx

[InsertCreativityHere]

Fixed!

[InsertCreativityHere]

I couldn't find a single reference to this _SliceCExe property anywhere.
Is there something special I'm missing or is this just properly dead code?

[bernardnormier]

I don't see any either.

[InsertCreativityHere]

This file was moved from tools to build some time ago.

Also there were some sentences that ended with 2 spaces instead of 1?
If this is intentional I can revert, but it seemed like just a typo to me.

[InsertCreativityHere]

Replaced by #4725.

I still like my script, but it's easier to do this regeneration with a build task.
This way we can re-use the existing logic for finding slicec.
Because really, finding slicec and the generator is 80% of this script.