[POS as a tab i2] Update WC plugin matching to use the file name in plugin path instead of matching by full plugin path

[jaclync]

For WOOMOB-899

Just one review is required.

Why

A (likely edge case) scenario was brought up when the WooComemrce plugin's plugin path can be altered by certain hosts or another plugin, like WooCommerce Beta Tester plugin as in WOOMOB-896. This means that one of the common plugin matching patterns in the app using the full plugin path wouldn't work anymore, resulting in unexpected behavior like the store not being able to access POS.

How

From a previous discussion pdfdoF-3pF-p2#comment-4655 with the web team, we concluded that matching by just the filename without extension (e.g. */woocommerce.* in the example of WC plugin) in the plugin path is the most durable solution so far. This PR just updates the plugin matching for the POS use case, while leaving other use cases for the Backlog.

Implementation

This PR adds a new storage extension method loadSystemPlugin(siteID:fileNameWithoutExtension:active:) to support POS plugin matching by file name without extension.

The implementation uses regex pattern matching with NSPredicate format MATCHES for precise filename matching to support:

• Supports both plugin types:
  • Single-file plugins: plugin-name.php
  • Folder-based plugins: folder/plugin-name.php
• Exact matching: Prevents false positives (e.g., searching "woocommerce" won't match "woocommerce-extended.php")
• Special character handling: Uses NSRegularExpression.escapedPattern(for:) to safely handle regex metacharacters in filenames

Steps to reproduce

Prerequisite: set up a JN store using the Woo Beta Tester plugin targeting trunk or a branch (example options screenshot in WOOMOB-896):

• Log in to the JN store --> the POS tab should become visible
• Tap on the POS tab --> it should enter POS items loaded state. before this PR, an ineligible UI is shown ("plugin not found")

Testing information

Tested in iPad mini iOS 18.5 simulator with WP store credentials login.

Screenshots

before	after

---

• I have considered if this change warrants user-facing release notes and have added them to RELEASE-NOTES.txt if necessary.

[wpmobilebot]

📲 You can test the changes from this Pull Request in WooCommerce iOS Prototype by scanning the QR code below to install the corresponding build.

	App Name	WooCommerce iOS Prototype
	Build Number	pr15931-322e50f
	Version	22.8
	Bundle ID	com.automattic.alpha.woocommerce
	Commit	322e50f
	Installation URL	574t3ikcmvi98

Automatticians: You can use our internal self-serve MC tool to give yourself access to those builds if needed.

[staskus]

👍 Looks good. I haven't found issues with the regex itself. As you mentioned, we should complete a backlog task replace all the other calls to loadSystemPlugin using fileNameWithoutExtension version to avoid mismatching behavior 👍