Use slog instead of logr

[MrAlias]

• Use the built in slog package to log instead of using logr.
• Replace WithLogLevel with WithLogger
  • Allow users to provide a fully-customized logger with their handler of choice instead of imposing a choice on them.
• Removes dependency on github.com/go-logr/zapr, go.uber.org/zap v1.27.0, and go.uber.org/multierr

Resolves #1104

Example Output

Raw:

{"time":"2024-09-11T17:29:35.700958753Z","level":"INFO","source":{"function":"go.opentelemetry.io/auto/internal/pkg/process.(*Analyzer).DiscoverProcessID","file":"/app/internal/pkg/process/discover.go","line":64},"msg":"found process","pid":754625}
{"time":"2024-09-11T17:29:35.723405405Z","level":"INFO","source":{"function":"go.opentelemetry.io/auto/internal/pkg/process.remoteAllocate.func1","file":"/app/internal/pkg/process/allocate.go","line":70},"msg":"Detaching from process","pid":754625}
{"time":"2024-09-11T17:29:35.723583269Z","level":"INFO","source":{"function":"go.opentelemetry.io/auto.NewInstrumentation","file":"/app/instrumentation.go","line":111},"msg":"target process analysis completed","pid":754625,"go_version":"1.23.1","dependencies":{"go.uber.org/multierr":"1.10.0","go.uber.org/zap":"1.27.0","std":"1.23.1"},"total_functions_found":2}
{"time":"2024-09-11T17:29:35.723973977Z","level":"INFO","source":{"function":"main.main","file":"/app/cli/main.go","line":134},"msg":"starting instrumentation..."}
{"time":"2024-09-11T17:29:35.731129749Z","level":"INFO","source":{"function":"go.opentelemetry.io/auto/internal/pkg/instrumentation.(*Manager).load","file":"/app/internal/pkg/instrumentation/manager.go","line":323},"msg":"loading probe","name":{"SpanKind":2,"InstrumentedPkg":"net/http"}}
{"time":"2024-09-11T17:29:36.079187915Z","level":"INFO","source":{"function":"go.opentelemetry.io/auto/internal/pkg/instrumentation.(*Manager).ConfigLoop","file":"/app/internal/pkg/instrumentation/manager.go","line":237},"msg":"Configuration provider closed, configuration updates will no longer be received"}
{"time":"2024-09-11T17:29:36.079275764Z","level":"INFO","source":{"function":"main.main.func3","file":"/app/cli/main.go","line":130},"msg":"instrumentation loaded successfully"}

Wrapped:

{
  "time": "2024-09-11T17:29:35.723973977Z",
  "level": "INFO",
  "source": {
    "function": "main.main",
    "file": "/app/cli/main.go",
    "line": 134
  },
  "msg": "starting instrumentation..."
},
{
  "time": "2024-09-11T17:29:35.731129749Z",
  "level": "INFO",
  "source": {
    "function": "go.opentelemetry.io/auto/internal/pkg/instrumentation.(*Manager).load",
    "file": "/app/internal/pkg/instrumentation/manager.go",
    "line": 323
  },
  "msg": "loading probe",
  "name": {
    "SpanKind": 2,
    "InstrumentedPkg": "net/http"
  }
},
{
  "time": "2024-09-11T17:29:36.079187915Z",
  "level": "INFO",
  "source": {
    "function": "go.opentelemetry.io/auto/internal/pkg/instrumentation.(*Manager).ConfigLoop",
    "file": "/app/internal/pkg/instrumentation/manager.go",
    "line": 237
  },
  "msg": "Configuration provider closed, configuration updates will no longer be received"
},
{
  "time": "2024-09-11T17:29:36.079275764Z",
  "level": "INFO",
  "source": {
    "function": "main.main.func3",
    "file": "/app/cli/main.go",
    "line": 130
  },
  "msg": "instrumentation loaded successfully"
}

[RonFed]

looks great