Performance: Hoist regexp.MustCompile out of functions

[vishnukothakapu]

Replaces regexp.MustCompile with regexp.Delayed from go.podman.io/storage/pkg/regexp for global regular expressions. This avoids compiling regular expressions during the global init scope, improving startup performance for all commands.
Additionally, where possible (such as in quadlet, mac-helper, and ps), the regex engine was stripped entirely and replaced with faster strings and loop checks to avoid any regex overhead altogether.
Tests are kept using regexp.MustCompile where applicable.

Fixes #29510

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Does this PR introduce a user-facing change?

None

[mheon]

LGTM

[Luap99]

Performance wise that actually has the opposite effect for most commands.
Compiling tje regex in the global init scope means every signle command must compile them over and over again, given podman is not a daemon and we run commands over and over again. Most code paths will never need the regex that was compiled so this is wasted time.

This was so bad we had to add our own go.podman.io/storage/pkg/regexp package to delay regex compilation until it is actually needed.
All user must use this, see c2b36be

[packit-as-a-service]

[NON-BLOCKING] Packit jobs failed. @podman-container-tools/packit-jobs please check. Everyone else, feel free to ignore.

[Honny1]

I have three things:

• is posbile to replace with a simple regex with different checks?
• Please put in the commit msg Fixes: #numOfIssueThatFixesThisCommit
• Also update the description, commit msg, etc...

[vishnukothakapu]

• is posbile to replace with a simple regex with different checks?

Yes @Honny1 , that's a great point. I went ahead and replaced the simple regexes in pkg/systemd/quadlet/unitdirs.go, cmd/podman-mac-helper/main.go, and pkg/ps/ps.go entirely with standard strings and loop checks. This avoids regex compilation overhead altogether in those paths. The more complex regex patterns have been kept as regexp.Delayed.

[Honny1]

Error: pkg/systemd/quadlet/unitdirs.go:226:10: undefined: numericRegex
make: *** [Makefile:525: bin/podman.cross.linux.amd64] Error 1

[Honny1]

I spotted only one issue. Otherwise, we are on good way.

[Luap99]

LGTM

[Honny1]

LGTM