sagemathgh-39008: Add Meson-specific settings to vscode settings

    
By default, the Meson VS Code extension changes the paths in
`settings.json` so that C++ intellisense is working. Here we set it up
correctly and prevent further overwrites.

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URL: sagemath#39008
Reported by: Tobias Diez
Reviewer(s): Dima Pasechnik

.vscode/settings.json

@@ -108,5 +108,11 @@
         "zmin"
     ],
     "editor.formatOnType": true,
-    "esbonio.sphinx.confDir": ""
+    "esbonio.sphinx.confDir": "",
+    // Don't update the settings.json file with values inferred from Meson (we provide them manually)
+    "mesonbuild.modifySettings": false,
+    // Use the Meson build system for C/C++ files
+    "C_Cpp.default.configurationProvider": "mesonbuild.mesonbuild",
+    // Use the compile_commands.json file generated by Meson for IntelliSense
+    "C_Cpp.default.compileCommands": "${workspaceFolder}/builddir/compile_commands.json"
 }