Add user properties: host_os_version, locale, and client_ide

[eliasyishak]

Closes out issues:

• Create a user property for the user's IDE #189
• Add host OS version and language as user properties #188

These extra user properties were provided by package:usage for flutter/flutter's legacy analytics.

The constructor will look like the below

// Development constructor points to dev GA4 instance; not
// to be used in production
final Analytics analytics = Analytics.development(
  tool: DashTool.flutterTool,
  flutterChannel: 'ey-test-channel',
  flutterVersion: 'Flutter 3.6.0-7.0.pre.47',
  clientIde: 'VSCode',
  dartVersion: 'Dart 2.19.0',
  // This can be set to true while testing to validate
  // against GA4 usage limitations (character limits, etc.)
  enableAsserts: false,
);

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[github-actions]

Package publishing

Package	Version	Status	Publish tag (post-merge)
package:unified_analytics	5.3.0	ready to publish	unified_analytics-v5.3.0
package:graphs	2.3.2-wip	WIP (no publish necessary)
package:cli_config	0.1.2	already published at pub.dev
package:extension_discovery	2.0.1-wip	WIP (no publish necessary)

Documentation at https://github.com/dart-lang/ecosystem/wiki/Publishing-automation.

[eliasyishak]

@bwilkerson I know the analysis server is already sending clientId in the event constructors... this PR isn't suggesting you need to change that, but you can add it to the Analytics constructor so that each event will contain the IDE being used