Feature request: apply sampling only after N occurrences

### Problem Statement

The sample rate applies to all error events. However, the first occurrence of an error is often very useful to know about -- for example, if an error occurs during internal testing before a feature is released. It would be really useful if we could configure different sampling rates based on the number of times the error has occurred (e.g. 100% for the first 100 occurrences and 5% after that).

### Solution Brainstorm

_No response_

### Product Area

Ingestion and Filtering

No files, tests, or entry points are identified in this feature request; begin by clarifying the ingestion and filtering component and the scope of “occurrences.” The work is ready to start only after the sampling behavior, configuration, and acceptance criteria are agreed.

Written by the indexing model from the issue text.