[PLAT-8604] Disable NSFileProtectionComplete for crash reports

[nickdowell]

Goal

Fix reporting of crashes that occur while data protection is enabled and the device is locked.

Crash reports were failing to be written, with diagnostic logs like the following:

[Bugsnag] [ERROR] Could not open file [...]/v1/KSCrashReports/swift-ios-CrashState.json for writing: Operation not permitted
INFO : BSG_KSCrashReport.c:1438: bsg_kscrashreport_writeStandardReport(): Writing crash report to [...]/v1/KSCrashReports/CrashReport-E1EEDC19-B397-48B5-A5E7-E45C9E980CD7.json
ERROR: BSG_KSCrashReport.c:1353: bsg_kscrw_i_openCrashReportFile(): Could not open crash report file [...]/v1/KSCrashReports/CrashReport-E1EEDC19-B397-48B5-A5E7-E45C9E980CD7.json: Operation not permitted
ERROR: BSG_KSCrashReport.c:258: bsg_kscrw_i_addJSONElementFromFile(): Could not open file [...]/v1/config.json: Operation not permitted

Changeset

If the default protection is NSFileProtectionComplete, changes the protection for the crash reports directory (and contents) and run_context to NSFileProtectionCompleteUnlessOpen.

NSFileProtectionCompleteUnlessOpen allows new files to be created while the device is locked, but once closed, cannot be opened again until the device is unlocked. This allows crash reports to be written while preserving security through data protection.

Stores config JSON in memory to allow inclusion in crash reports without reading from a file which may be inaccessible.

Testing

Manually verified crash reporting using test app.

[github-actions]

	1 Warning
⚠️	This PR modifies BSGRunContext.h but does not change BSGRUNCONTEXT_VERSION

Bugsnag.framework binary size increased by 256 bytes from 815,216 to 815,472

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