crosscluster/logical: set UDF function name from SQL input

[stevendanna]

First commit is #127024

See individual commits.

[cockroach-teamcity]

This change is 

[rafiss]

Reviewable status: complete! 0 of 0 LGTMs obtained (waiting on @azhu-crl, @dt, and @stevendanna)

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pkg/ccl/crosscluster/logical/logical_replication_job.go line 379 at r5 (raw file):

				// processors. This makes it a fragile to
				// renames.
				fnName = fmt.Sprintf("%s.%s",

we could pass it by OID instead. in case you weren't aware, we already have this syntax:

root@localhost:26257/defaultdb> CREATE FUNCTION add(a INT, b INT) RETURNS INT LANGUAGE SQL AS $$ SELECT a + b; $$;
CREATE FUNCTION

Time: 28ms total (execution 20ms / network 8ms)

root@localhost:26257/defaultdb> select 'add'::regproc::oid;
   oid
----------
  100105
(1 row)

Time: 2ms total (execution 2ms / network 1ms)

root@localhost:26257/defaultdb> SELECT [FUNCTION 100105](1, 2);
  add
-------
    3
(1 row)

[dt]

Oh nice, I like that via-OID call that sidesteps all resolution messiness.

[stevendanna]

Oh cool, it works across databases as well. Very useful!

[stevendanna]

Well that cleans things up rather nicely.

[Jeremyyang920]

Changes lookgood to me, but will defer to Rafi with more context on the UDF work. I'll wait for these changes to then rebase create_logical_replication_stmt onto my open PR now.

[stevendanna]

bors r=dt

[craig]

Build succeeded:

• lint
• docker_image_amd64
• unit_tests
• local_roachtest_fips
• local_roachtest
• linux_amd64_build
• windows_build
• examples_orms
• linux_amd64_fips_build
• acceptance
• macos_amd64_build
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• macos_arm64_build
• linux_arm64_build

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You might need to create your backport manually using the backport tool.

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error creating merge commit from 46d61f8 to blathers/backport-release-24.2-127428: POST https://api.github.com/repos/cockroachdb/cockroach/merges: 409 Merge conflict []

you may need to manually resolve merge conflicts with the backport tool.

Backport to branch 24.2.x failed. See errors above.

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[msbutler]

@stevendanna i believe the backport for this needs to merge after #127538