fix: filter targetFilter to page-level targets to prevent connection timeouts

[kevmo314]

Summary

When connecting to a browser with many open tabs via --browserUrl or --wsEndpoint, the MCP server can time out with Network.enable timed out because Puppeteer attaches to every target (iframes, service workers, shared workers, webviews, background pages) and sends CDP initialization commands (Network.enable, Page.enable, Runtime.enable, etc.) to each one.

Frozen or suspended background tabs don't respond to these commands, causing the connection to hang until the protocol timeout (180s) is reached. A typical browsing session can easily have 50-60+ targets but only ~7 actual pages.

Fix

Restricts targetFilter in makeTargetFilter() to only attach to page and other type targets. This is safe because:

• Iframes within pages are still accessible via page.frames() — they don't need to be separate targets
• Network/console events work through the page-level CDP session
• Extension service workers (--categoryExtensions) are disabled by default and were already filtered out by the chrome-extension:// URL prefix filter

Before/After

With ~58 browser targets (7 pages, 24 iframes, 13 service workers, 9 workers, 4 background pages, 1 webview):

• Before: puppeteer.connect() hangs for 180s then times out
• After: puppeteer.connect() attaches to ~7-9 targets and completes quickly

Test plan

• tsc --noEmit passes
• Verify list_pages returns all open pages
• Verify select_page + page interaction tools work
• Verify network request listing works on selected page
• Verify console message collection works
• Test with --categoryExtensions to confirm extension tools still work when launched (not connected)

🤖 Generated with Claude Code

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[OrKoN]

this is not not true, those targets are needed.

[OrKoN]

Thanks for the PR! are you sure you are not hitting this issue with frozen tabs instead #775 ?

[OrKoN]

Iframes within pages are still accessible via page.frames() — they don't need to be separate targets

This is false as well.

[kevmo314]

Thanks for the PR! are you sure you are not hitting this issue with frozen tabs instead #775 ?

Ah it's possible this is the real issue I'm hitting, thanks for the link!