Automatic metric naming from code

### Problem Statement

It would be nice if recording metrics didn’t always require coming up with a name. Instead of passing a string, you could record a metric based on where it’s called from in the code. The SDK would capture the call site, and Sentry could de-obfuscate it using source maps to show the real function or location.

### Solution Brainstorm

_No response_

### Product Area

Explore

The issue names no files, tests, or entry points to inspect. Begin by clarifying which SDKs and metric APIs are in scope, how call sites should be captured, and how source-map de-obfuscation should work; the work is done when those decisions are specified and covered by tests.

Written by the indexing model from the issue text.