Prevent telemetry exporters from feeding back into themselves (#40658)

## Why

Telemetry transport and storage can emit their own diagnostics, causing exports
or SQLite writes to recursively generate more telemetry.

## What changed

- Exclude `h2` spans from trace export so OTLP transport activity cannot trigger
  additional OTLP exports.
- Exclude all `sqlx`, `sqlx_core`, and `sqlx_sqlite` diagnostics from the SQLite
  log sink, including when no external subscriber filter is installed.
- Keep similarly named targets such as `sqlx_application` eligible for storage.

## Testing

- Extend the SQLite log-filter test to cover the broader SQLx exclusion and the
  unrelated-target case.

GitOrigin-RevId: 13a832e1f228e9564a31cc08f00add286342bac1