xactfetch: Save Playwright trace for failed runs

Playwright has a nifty feature called the [Trace Viewer][0], which you
can use to observe the state of the page at any given point during the
browsing session.  This should make troubleshooting failures a lot
easier.

[0]: https://playwright.dev/python/docs/trace-viewer-intro

xactfetch.py

@@ -722,7 +722,9 @@ async def amain() -> None:
     failed = False
     async with async_playwright() as pw, secrets:
         browser = await pw.chromium.launch(headless=False)
-        page = await browser.new_page()
+        context = await browser.new_context()
+        await context.tracing.start(screenshots=True, snapshots=True)
+        page = await context.new_page()
         banks = sys.argv[1:] or list(ACCOUNTS.keys())
         if 'commerce' in banks:
             if not await download_commerce(
@@ -734,6 +736,14 @@ async def amain() -> None:
                 page, secrets, end_date, token, importer
             ):
                 failed = True
+        if failed:
+            await context.tracing.stop(path='trace.zip')
+            with open('trace.zip', 'rb') as f:
+                await ntfy(
+                    'Downloading one or more transaction lists failed.',
+                    attach=f.read(),
+                    filename='trace.zip',
+                )
     raise SystemExit(1 if failed else 0)