Fix panic during merge when FK is dropped and re-added on a branch with a composite PK child table

[elianddb]

Fix #10676
dolt merge could panic with index out of range when one branch dropped and re-added a foreign key (creating a new backing index) while the other branch had new rows in a child table with a composite primary key. This fix limits the FK column type compatibility check to only the columns relevant to the foreign key, ignoring extra primary key columns that are not part of the FK relationship.

[coffeegoddd]

@elianddb DOLT

read_tests	from_latency	to_latency	percent_change
covering_index_scan	0.58	0.56	-3.45
groupby_scan	10.09	10.09	0.0
index_join	1.86	1.86	0.0
index_join_scan	1.39	1.42	2.16
index_scan	21.89	22.28	1.78
oltp_point_select	0.27	0.27	0.0
oltp_read_only	5.28	5.28	0.0
select_random_points	0.53	0.54	1.89
select_random_ranges	0.55	0.56	1.82
table_scan	21.89	21.89	0.0
types_table_scan	66.84	65.65	-1.78

write_tests	from_latency	to_latency	percent_change
oltp_delete_insert	6.32	6.32	0.0
oltp_insert	3.13	3.13	0.0
oltp_read_write	11.45	11.45	0.0
oltp_update_index	3.19	3.19	0.0
oltp_update_non_index	3.13	3.13	0.0
oltp_write_only	6.09	6.09	0.0
types_delete_insert	6.91	6.91	0.0

[coffeegoddd]

@elianddb DOLT

comparing_percentages
100.000000 to 100.000000

version	result	total
2674a18	ok	5937471

version	total_tests
2674a18	5937471

correctness_percentage
100.0

[coffeegoddd]

@elianddb DOLT

test_name	from_latency_p95	to_latency_p95	percent_change
tpcc-scale-factor-1	61.08	61.08	0.0

test_name	from_server_name	from_server_version	from_tps	to_server_name	to_server_version	to_tps	percent_change
tpcc-scale-factor-1	dolt	24e549c	38.17	dolt	bda18ff	37.61	-1.47

[angelamayxie]

looks good except fix the comments

[coffeegoddd]

@elianddb DOLT

comparing_percentages
100.000000 to 100.000000

version	result	total
2b376c5	ok	5937471

version	total_tests
2b376c5	5937471

correctness_percentage
100.0

[coffeegoddd]

@elianddb DOLT

comparing_percentages
100.000000 to 100.000000

version	result	total
bda18ff	ok	5937471

version	total_tests
bda18ff	5937471

correctness_percentage
100.0

[jycor]

LGTM

[github-actions]

@coffeegoddd DOLT

name	add_cnt	delete_cnt	update_cnt	latency
adds_only	60000	0	0	0.65
adds_updates_deletes	60000	60000	60000	3.19
deletes_only	0	60000	0	1.5
updates_only	0	0	60000	1.9

[github-actions]

@coffeegoddd DOLT

test_name	detail	row_cnt	sorted	mysql_time	sql_mult	cli_mult
batching	LOAD DATA	10000	1	0.06	1.67
batching	batch sql	10000	1	0.07	1.71
batching	by line sql	10000	1	0.07	1.86
blob	1 blob	200000	1	0.9	4.1	4.44
blob	2 blobs	200000	1	0.89	4.54	4.44
blob	no blob	200000	1	0.89	2.8	2.74
col type	datetime	200000	1	0.84	2.58	2.52
col type	varchar	200000	1	0.69	3.59	3.55
config width	2 cols	200000	1	0.81	2.58	2.46
config width	32 cols	200000	1	1.96	3.04	2.59
config width	8 cols	200000	1	0.99	2.75	2.49
pk type	float	200000	1	0.89	2.7	2.27
pk type	int	200000	1	0.78	2.73	2.58
pk type	varchar	200000	1	1.55	1.75	1.58
row count	1.6mm	1600000	1	5.85	2.93	2.73
row count	400k	400000	1	1.48	2.85	2.68
row count	800k	800000	1	2.96	2.88	2.68
secondary index	four index	200000	1	3.66	1.3	1.11
secondary index	no secondary	200000	1	0.88	2.86	2.77
secondary index	one index	200000	1	1.1	2.63	2.34
secondary index	two index	200000	1	2.01	1.77	1.72
sorting	shuffled 1mm	1000000	0	5.04	2.82	2.65
sorting	sorted 1mm	1000000	1	5.11	2.79	2.61