add merge rollback logic

[ajtmccarty]

fixes #4448
IFC-732

moves the call to merge a branch out of a transaction b/c a large merge was too big of a transaction and caused an OOM error
instead of a transaction, the merge is inside of a try-except block that will use a new query to roll the merge back

• also fixes a bug in the merge query that prevented IS_RELATED edges from getting set to status="deleted" in some scenarios where the was a conflict
• and removes the conflict_resolution argument to the merge, b/c conflict information is stored in the diff now

[codspeed-hq]

CodSpeed Performance Report

Merging #4818 will degrade performances by 18.72%

_{Comparing ajtm-10312024-merge-rollback (a62d0f2) with stable (b2928f9)}

Summary

❌ 1 regressions
✅ 9 untouched benchmarks

⚠️ Please fix the performance issues or acknowledge them on CodSpeed.

Benchmarks breakdown

	Benchmark	stable	ajtm-10312024-merge-rollback	Change
❌	test_schemabranch_duplicate	309.7 µs	381 µs	-18.72%