feat(normalization): Trim tag keys & values

[jjbayer]

We've been dropping event tag values when they are too long: 7af05d4

SDKs are removing truncation on their side, so Relay should truncate instead of dropping to create the same end-to-end behavior for the product.

Fixes INGEST-538.

---

Note

Switch handling of overlong tag keys/values from dropping to trimming with remarks, and update tests accordingly.

• Tag Trimming Behavior:
  • Implement trimming (with remarks) for overlong tag keys/values in TrimmingProcessor tests, replacing previous behavior that dropped them.
• Tests:
  • Remove normalize::tests::test_too_long_tags that expected drop-on-too-long in relay-event-normalization/src/normalize/mod.rs.
  • Add trimming::tests::test_too_long_tags verifying trimmed Tags PairList snapshots in relay-event-normalization/src/trimming.rs.
  • Adjust imports to include PairList where needed.

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[linear]

INGEST-538 Truncate tag values instead of dropping them

[Dav1dde]

Not sure if I am missing something, this looks like there were only changes made to tests?