iterateChangedRecent: skip DB entries within file range

[sudeepdino008]

Closes #20356

• Adjust fromTxNum for the DB iterator in iterateChangedRecent to max(fromTxNum, files.EndTxNum()), matching the existing pattern in HistoryKeyTxNumRange
• Prevents reading prunable DB entries that are already covered by segment files
• Add TestHistory_IterateChangedRecent_SkipsFileRange: builds files, prunes DB entries within the file range, verifies HistoryRange spanning both files and DB still returns correct results

[Copilot]

Pull request overview

Fixes an inconsistency in HistoryRange when the requested range spans both frozen segment files and the DB by ensuring the DB iterator does not start inside the file-covered txNum range (which may be pruned).

Changes:

• Adjust iterateChangedRecent to start the DB scan at max(fromTxNum, files.EndTxNum()), aligning behavior with HistoryKeyTxNumRange.
• Add a regression test that prunes DB entries within the file range and verifies HistoryRange still returns complete results across the file/DB boundary.

Reviewed changes

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

File	Description
db/state/history.go	Skips DB iteration for txNums already covered by frozen files by raising the DB iterator start txNum to files.EndTxNum().
db/state/history_test.go	Adds a regression test that prunes DB entries inside the file-covered range and validates HistoryRange output remains correct.

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[Copilot]

The write transaction from db2.BeginRw(ctx) isn’t guarded by defer rwTx.Rollback(). If any require.* fails before the commit, the tx can remain open and leak resources / affect later test cleanup. Add a rollback defer immediately after BeginRw (Commit will make it a no-op).

Suggested change

	require.NoError(err)
	require.NoError(err)
	defer rwTx.Rollback()