opt: route descriptor lookups for AFTER triggers through cache

[mgartner]

bench/rttananlysis: document directions for running tests

These tests have a non-conventional construction that make it hard to
determine how they can be run. Each subset of tests is not a typical Go
function like func TestAThing(t *testing.T) { ... } that can be easily
searched for. A few comments have been added to explain how the tests
can be run.

Release note: None

bench/rttanalysis: add test case with an after trigger

Release note: None

opt: route descriptor lookups for AFTER triggers through cache

This commit applies the fix in #144217 for BEFORE triggers to AFTER
triggers. See that PR for more details.

Fixes #144211

Release note (performance improvement): After triggers now perform the
descriptor lookup for TG_TABLE_SCHEMA against a cache. This can
significantly reduce trigger planning latency.

opt: warn about performance of (*optCatalog).FullyQualifiedName

Release note: None

[cockroach-teamcity]

This change is 

[fqazi]

@fqazi reviewed 2 of 2 files at r1, 2 of 2 files at r2, 2 of 2 files at r3, all commit messages.
Reviewable status: complete! 1 of 0 LGTMs obtained (waiting on @DrewKimball)

[DrewKimball]

Thanks! It might also be worth adding a comment to FullyQualifiedName to warn people away from using it over methods that go through the cache.

@DrewKimball reviewed 2 of 2 files at r1, 2 of 2 files at r2, 2 of 2 files at r3, all commit messages.
Reviewable status: complete! 2 of 0 LGTMs obtained (waiting on @mgartner)

[mgartner]

It might also be worth adding a comment to FullyQualifiedName to warn people away from using it over methods that go through the cache.

The interface already mentions this:

cockroach/pkg/sql/opt/cat/catalog.go

Lines 263 to 264 in 59e8ced

	// - this call may involve a database operation so it shouldn't be used in
	// performance sensitive paths;

I copied these notes to the opt catalog implementation too.

[mgartner]

TFTRs!

bors r+

[craig]

Build succeeded:

• unit_tests
• linux_amd64_fips_build
• lint
• docker_image_amd64
• examples_orms
• local_roachtest
• linux_amd64_build
• check_generated_code
• acceptance
• local_roachtest_fips

[blathers-crl]

Based on the specified backports for this PR, I applied new labels to the following linked issue(s). Please adjust the labels as needed to match the branches actually affected by the issue(s), including adding any known older branches.

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Issue #144211: branch-release-25.3, branch-release-25.4.

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[blathers-crl]

Encountered an error creating backports. Some common things that can go wrong:

1. The backport branch might have already existed.
2. There was a merge conflict.
3. The backport branch contained merge commits.

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

---

💡 Consider backporting to the fork repo instead of the main repo. See instructions for more details.

error creating merge commit from 5f69f7b to blathers/backport-release-25.2-158708: 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 25.2.x failed. See errors above.

---

💡 Consider backporting to the fork repo instead of the main repo. See instructions for more details.

error creating merge commit from 364a865 to blathers/backport-release-25.3-158708: 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 25.3.x failed. See errors above.

---

💡 Consider backporting to the fork repo instead of the main repo. See instructions for more details.

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