feat: add configuration object for init in objc

[kattrali]

Adds additional start selectors for the Objective-C interface, mostly to ease configuring with different options (accounting for the lack of default parameters).

Removes the public unstable APIs for initializing fatal issue reporting in favor of the new configuration object.

Examples

Creating a configuration:

CAPConfiguration *config = [[CAPConfiguration alloc]
                              initWithEnableFatalIssueReporting:YES
                              enableURLSessionIntegration:YES];

CAPConfiguration *config = [[CAPConfiguration alloc]
                              initWithEnableFatalIssueReporting:YES
                              enableURLSessionIntegration:YES
                              sleepMode:CAPSleepModeInactive];

Starting with a config:

[CAPLogger startWithAPIKey:@"<some key>"
           sessionStrategy:[CAPSessionStrategy activityBased]
             configuration:config];

[CAPLogger startWithAPIKey:@"<some key>"
           sessionStrategy:[CAPSessionStrategy activityBased]
             configuration:config
                    apiURL:[NSURL URLWithString:@"<some url>"]];