Module UpdateValue 

Configuration value update and persistence.

Implements UpdateConfigurationValue for MountainEnvironment. Resolves the write target to a concrete settings.json path, performs a read-modify-write, then invalidates the parse cache and triggers a full re-merge so subsequent reads reflect the change.

Target resolution

ConfigurationTarget	Write destination
User / UserLocal	<app-config>/settings.json
Workspace	workspace settings.json
WorkspaceFolder	<first-folder>/.vscode/settings.json
Memory	in-memory merged map only; no disk write
Default / Policy	error - read-only by spec

Passing Value::Null as the new value removes the key from the target file rather than writing a null literal, matching VS Code’s “reset to default” behaviour.

Functions

update_configuration_value 🔒

Updates a configuration value in the appropriate settings.json file.