refactor: replace filepath.Walk with filepath.WalkDir

[Gofastasf]

Replace filepath.Walk with filepath.WalkDir.

filepath.WalkDir, introduced in Go 1.16, is more performant as it avoids creating unnecessary intermediate os.FileInfo objects. While filepath.Walk calls os.Lstat for every file or directory to retrieve os.FileInfo, filepath.WalkDir provides a fs.DirEntry, which includes file type information without requiring a stat call.

This change reduces unnecessary system calls and aligns with modern Go practices for directory traversal.

[blathers-crl]

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[cockroach-teamcity]

All committers have signed the CLA.

[cockroach-teamcity]

This change is 

[blathers-crl]

Thank you for updating your pull request.

My owl senses detect your PR is good for review. Please keep an eye out for any test failures in CI.

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[RaduBerinde]

Thanks!

Reviewable status: complete! 1 of 0 LGTMs obtained (waiting on @aa-joshi, @arjunmahishi, @Gofastasf, @golgeek, @kev-cao, @kyle-a-wong, @srosenberg, and @wenyihu6)

---

pkg/cli/debug_merge_logs.go line 353 at r1 (raw file):

	var files []fileInfo
	for _, p := range paths {
		// NB: come go1.16, we should use WalkDir here as it is more efficient.

[nit] remove comment

[RaduBerinde]

Reviewable status: complete! 1 of 0 LGTMs obtained (waiting on @aa-joshi, @arjunmahishi, @Gofastasf, @golgeek, @kev-cao, @kyle-a-wong, @srosenberg, and @wenyihu6)

[blathers-crl]

Thank you for updating your pull request.

Before a member of our team reviews your PR, I have some potential action items for you:

• We notice you have more than one commit in your PR. We try break logical changes into separate commits, but commits such as "fix typo" or "address review commits" should be squashed into one commit and pushed with --force
• Please ensure your git commit message contains a release note.
• When CI has completed, please ensure no errors have appeared.

_{🦉 Hoot! I am a Blathers, a bot for CockroachDB. My owner is dev-inf.}

[blathers-crl]

Thank you for updating your pull request.

Before a member of our team reviews your PR, I have some potential action items for you:

• We notice you have more than one commit in your PR. We try break logical changes into separate commits, but commits such as "fix typo" or "address review commits" should be squashed into one commit and pushed with --force
• Please ensure your git commit message contains a release note.
• When CI has completed, please ensure no errors have appeared.

_{🦉 Hoot! I am a Blathers, a bot for CockroachDB. My owner is dev-inf.}

[Gofastasf]

@RaduBerinde Hey there seems to be some build issue but its from Github CI deprecated so I don't need to care ? Is this okay to get merged ?

This is my first PR :)

[RaduBerinde]

bors r+

[craig]

Build failed:

• lint

[RaduBerinde]

=== CONT  TestLint/TestCrlfmt
    gen-lint_test.go:1787: 
        diff -u old/cmd/whoownsit/whoownsit.go new/cmd/whoownsit/whoownsit.go
        --- old/cmd/whoownsit/whoownsit.go	2025-01-16 16:24:58.609856355 +0000
        +++ new/cmd/whoownsit/whoownsit.go	2025-01-16 16:24:58.609856355 +0000
        @@ -12,8 +12,8 @@
         import (
         	"flag"
         	"fmt"
        -	"log"
         	"io/fs"
        +	"log"
         	"os"
         	"path/filepath"
         	"strings"
    gen-lint_test.go:1802: run the following to fix your formatting:
        
        bin/crlfmt "-fast" "-ignore" "zcgo*|\\.(pb(\\.gw)?)|(\\.[eo]g)\\.go|/testdata/|^sql/parser/sql\\.go$|(_)?generated(_test)?\\.go$|^sql/pgrepl/pgreplparser/pgrepl\\.go$|^sql/plpgsql/parser/plpgsql\\.go$" "-tab" "2" "-w" "/github-actions-runner/_work/cockroach/cockroach/pkg"
        
        Don't forget to add amend the result to the correct commits.
    --- FAIL: TestLint/TestCrlfmt (6.34s)

Yuo need to apply that patch or run crlfmt (which is our own "stronger" gofmt).

[blathers-crl]

Your pull request contains more than 1000 changes. It is strongly encouraged to split big PRs into smaller chunks.

Thank you for updating your pull request.

My owl senses detect your PR is good for review. Please keep an eye out for any test failures in CI.

_{🦉 Hoot! I am a Blathers, a bot for CockroachDB. My owner is dev-inf.}

[RaduBerinde]

Sorry, I guess the command line is outdated, we don't want to reformat tons of generated code. Just run crlfmt on the files you've changed (we usually set it up in the editor).

[Gofastasf]

@RaduBerinde Fixed the linting error.

[RaduBerinde]

Thanks, let's try again.

bors r+

[craig]

Build succeeded:

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