Add SentryLogsLogger forwarding to Sentry Structured Logs

[mSimota]

• New SentryLogsLogger LoggerService that forwards all levels to SentrySDK.logger with code.file/code.function/code.line attributes and parameter userInfo attached per log; tag userInfo goes to scope.
• Level mapping: verbose->trace, debug->debug, info->info, warning->warn, error->error.
• Does not start the SDK by default (composable next to SentryLogger, which owns SentrySDK.start); init(startingSDKWith:) for standalone use forces options.enableLogs = true.
• New SentryUserIdentity helper wrapping SentrySDK.setUser so host apps do not need to link Sentry directly.
• Implement missing removeUserInfo on SentryLogger.
• Bump sentry-cocoa minimum to 9.0.0 (stable structured logs API).

Description

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Changes

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• [Change 1]
• [Change 2]

Related Issue(s)

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Checklist

• I have tested this code on my local machine and it works as expected.
• I have added necessary documentation and comments.
• I have added unit tests and they all pass.
• I have followed the project's code style guidelines.
• I have updated the README file (if applicable).