PIR: Add debug scan option

[landomen]

Task/Issue URL: https://app.asana.com/1/137249556945/project/492600419927320/task/1212697400140246?focus=true

Description

Adds debug scan option that runs broker scan steps on a visible WebView

Steps to test this PR

• Ensure you have at least one profile query added
• Go to PIR Dev Settings -> Scan
• Select a broker from the new dropdown menu
• Click Debug Scan and confirm that a WebView is visible and steps are executed (note that sometimes the scan is so fast the screen closes immediately)

UI changes

UI changes in the PIR Dev settings screen

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Note

Adds a developer-facing debug scan flow that runs broker scan steps in a visible WebView and a minimal UI to trigger it.

• PirScan: introduces debugExecute(brokers, WebView) to execute parsed scan steps sequentially on a provided WebView; integrates with existing runner lifecycle and logging
• New PirDevWebViewActivity with DebugType to route between SCAN (PirScan) and OPT_OUT (PirOptOut), and stops the correct component on destroy
• Dev Scan screen: adds broker dropdown and "Debug Scan" button; loads active brokers and launches the WebView activity with selected broker
• Adds supporting strings and layout changes

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