/go/{cmd,libraries} check for valid dbs, close opened dbs on error

[coffeegoddd]

No description provided.

[Copilot]

Pull request overview

This PR adds proper cleanup of DoltDB resources in the multi-repo environment setup. It tracks opened environments during MultiEnvForDirectory, closes them on error, and adds a Close() method to MultiRepoEnv for orderly shutdown. It also adds a defensive validity check in newDatabase before attempting to use the database.

Changes:

• Track opened DoltEnvs during MultiEnvForDirectory and close their DoltDBs if the function fails partway through.
• Add a Close() method on MultiRepoEnv to close all held DoltDB instances.
• Add a validity check in newDatabase to return a clear error if the DoltEnv is not valid.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 1 comment.

File	Description
go/libraries/doltcore/env/multi_repo_env.go	Track opened envs for cleanup on error; add Close() method
go/cmd/dolt/commands/engine/utils.go	Add validity check in newDatabase
go/libraries/doltcore/env/multi_repo_env_test.go	Add test for MultiRepoEnv.Close()

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[coffeegoddd]

goes with dolthub/driver#190 to fix #10687

[coffeegoddd]

@coffeegoddd DOLT

read_tests	from_latency	to_latency	percent_change
covering_index_scan	0.55	0.57	3.64
groupby_scan	9.91	9.91	0.0
index_join	1.82	1.82	0.0
index_join_scan	1.39	1.39	0.0
index_scan	21.89	21.89	0.0
oltp_point_select	0.27	0.27	0.0
oltp_read_only	5.28	5.28	0.0
select_random_points	0.53	0.53	0.0
select_random_ranges	0.55	0.55	0.0
table_scan	22.28	21.89	-1.75
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	11.24	11.24	0.0
oltp_update_index	3.19	3.19	0.0
oltp_update_non_index	3.13	3.13	0.0
oltp_write_only	5.99	5.99	0.0
types_delete_insert	6.79	6.79	0.0

[coffeegoddd]

@coffeegoddd DOLT

comparing_percentages
100.000000 to 100.000000

version	result	total
c0f7ec8	ok	5937471

version	total_tests
c0f7ec8	5937471

correctness_percentage
100.0

[reltuk]

LGTM!

[coffeegoddd]

@coffeegoddd 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	1bd70a3	37.87	dolt	c0f7ec8	38.21	0.9