Add initial logger implementation

[giortzisg]

Closes #1000.

Example usage of logger

package main

import (
	"context"
	"github.com/getsentry/sentry-go"
	"github.com/getsentry/sentry-go/attribute"
	"time"
)

func main() {
	err := sentry.Init(sentry.ClientOptions{
		Dsn:        "",
		EnableLogs: true,
	})
	if err != nil {
		panic(err)
	}
	defer sentry.Flush(2 * time.Second)

	ctx := context.Background()
	logger := sentry.NewLogger(ctx)

	// you can use the logger like [fmt.Print]
	logger.Info(ctx, "Expecting ", 2, " params")
	// or like [fmt.Printf]
	logger.Infof(ctx, "format: %v", "value")

	// and you can also set attributes on the log like this
	logger.SetAttributes(
		attribute.Int("key.int", 42),
		attribute.Bool("key.boolean", true),
		attribute.Float64("key.float", 42.4),
		attribute.String("key.string", "string"),
	)
	logger.Warnf(ctx, "I have params %v and attributes", "example param")
}

[codecov]

Codecov Report

Attention: Patch coverage is 90.67797% with 22 lines in your changes missing coverage. Please review.

Project coverage is 85.42%. Comparing base (64de096) to head (74a43a0).
Report is 2 commits behind head on master.

Files with missing lines	Patch %	Lines
log.go	91.66%	10 Missing and 1 partial ⚠️
batch_logger.go	84.48%	8 Missing and 1 partial ⚠️
transport.go	91.66%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #1010      +/-   ##
==========================================
+ Coverage   85.12%   85.42%   +0.29%     
==========================================
  Files          53       55       +2     
  Lines        5276     5487     +211     
==========================================
+ Hits         4491     4687     +196     
- Misses        640      655      +15     
  Partials      145      145              

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[AbhiPrasad]

Saw this was in progress so did a preliminary review! Do you mind also adding some examples in the PR description of how log should be configured and used with this PR?

[giortzisg]

Thanks for the review Abhi. Will also add examples, nice catch.

[cleptric]

For Debug: true:

Sending info event [a710bb92af79490b9135782c8924d613] to o1.ingest.us.sentry.io project:

instead we should emit something like

Sending X log events [a710bb92af79490b9135782c8924d613] to o1.ingest.us.sentry.io project:

[cleptric]

Once https://github.com/getsentry/sentry-go/pull/1010/files/d40ff0a677f0d3d3b54ba2a0ae594ce85837d15d#r2086096970 is addressed, we can get this merged