Trim event title to a maximum length in grouper

[Kuchizu]

Trims event title to 1000 chars

[Copilot]

Pull request overview

This PR adds event-title trimming in the Grouper worker pipeline to cap excessively long titles (keeping hashing and stored payload consistent) and adds a regression test to validate the trimming behavior.

Changes:

• Add DataFilter.trimEventTitle() to trim event.title to 1000 characters (plus an ellipsis when trimmed).
• Invoke title trimming during GrouperWorker.handleInternal() before unique-hash calculation.
• Add a unit test ensuring long titles are trimmed before persisting.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 2 comments.

File	Description
workers/grouper/tests/index.test.ts	Adds coverage asserting long titles are truncated and end with an ellipsis.
workers/grouper/src/index.ts	Calls title trimming prior to computing the event’s unique hash (and affects downstream grouping/saving).
workers/grouper/src/data-filter.ts	Introduces title-trimming logic in DataFilter using the shared rightTrim() helper.

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[Copilot]

Pull request overview

Copilot reviewed 5 out of 5 changed files in this pull request and generated 3 comments.

[Copilot]

Pull request overview

Copilot reviewed 5 out of 5 changed files in this pull request and generated no new comments.

Comments suppressed due to low confidence (2)

workers/grouper/src/data-filter.ts:15

• PR description says the event title should be trimmed to 1000 chars, but this implementation uses MAX_TITLE_LENGTH = 400 (and the tests expect 401 including the ellipsis from rightTrim). Since the grouping hash is derived from task.payload.title, a lower-than-intended cap increases the chance of unrelated events collapsing into the same group. Please align the limit (and corresponding tests/PR description) to the intended maximum.

/**
 * Maximum length for event title before appending ellipsis
 */
const MAX_TITLE_LENGTH = 400;

workers/grouper/src/index.ts:212

• This comment is slightly misleading: the grouping hash is computed only from catcherType + task.payload.title, so the key reason to run DataFilter here is to ensure title trimming happens before hashing. Consider rewording to avoid implying other payload fields affect the hash.

    /**
     * Filter event data before hashing so hash and stored event stay consistent.
     */