[Bug]: Paykit payment-request sheet clips and does not open automatically (canary #3) #1404

Twin: synonymdev/bitkit-ios#863
Refs: #1407

What happened?

During Pubky Shop canary #3 (fresh profile The Piotr 3, order c62d186d, pay ₿1,753 — payment succeeded), several Paykit payment-request UX nits on Android:

1. Notification without auto-open — Payment bell / notification arrived, but Bitkit did not automatically present the pay / payment-request sheet. Had to open it manually.
2. Sheet sizing / scroll — The Payment Request sheet is not correctly sized. You can scroll it so content clips: either the large amount is cut off at the top, or the slide-to-pay control is cramped / partially covered at the bottom (system nav overlap).

Payment itself completed (Shop Payment seen). This ticket is UX polish / layout from that successful path; the slow pay sheet and confirmation are tracked in #1407 — not delivery failure (#1402 is the restore/recovery_required case).

Marketplace canary thread: BitcoinErrorLog/pubky-marketplace#54.

Expected behavior

1. When a Shop/Paykit payment request arrives while Bitkit is in foreground (or user taps the payment notification), the payment-request / pay sheet should open (or product should document that bell = notify-only). Related work: #1350.
2. Payment Request sheet should fit the viewport without clipping the amount or the slide-to-pay control; scroll should not hide primary chrome.

Steps to Reproduce

1. Fresh Bitkit mainnet profile; add seller Pav C Tester as contact.
2. Checkout a Pubky Shop listing that delivers a private Paykit payment request (~1k sats + payment code).
3. Keep Bitkit open / watch for payment notification / bell.
4. Observe: bell/notify without auto sheet; open pay manually.
5. On Payment Request sheet, scroll — amount clips at top and/or slider is cramped at bottom.

Logs / Screenshots / Recordings

Sheet top OK (slider visible)	Scrolled — amount clipped

Session logs:

bitkit_logs_2026-10-01_09-44-08.zip

09:23:59 WARN  PaykitPaymentRequestRepo — Timed out inspecting payment request support for 'pubkyad…'
09:24:35 WARN  PaykitPaymentRequestRepo — Timed out inspecting payment request support for 'pubkyad…'
09:26:24 INFO  PrivatePaykitRepo — Opened private Paykit payment for 'pubkyad…xmnjdcy'
09:26:45 INFO  AppViewModel — Decoded incoming Paykit payment request target
09:27:14 INFO  PrivatePaykitRepo — Consumed private Paykit payment list version 0 …
09:27:31 INFO  Keychain — Upserted 'PAYKIT_PRESENTED_PAYMENT_REQUESTS'
09:27:48 INFO  Keychain — Upserted 'PAYKIT_PRESENTED_PAYMENT_REQUESTS'
09:27:54 INFO  Keychain — Upserted 'PAYKIT_PENDING_PAYMENT_PROOFS'
09:27:59 INFO  LightningService — Sending 1753 sats to bc1qtnxlssr8x7pwas3xasqz8zzrkmz6gru7prpqkq, satsPerVByte=1
09:27:59 INFO  AppViewModel — Onchain send result txid: a71b5a8e…
09:29:47 DEBUG Keychain — Deleted 'PAYKIT_PENDING_PAYMENT_PROOFS'

~46s between Decoded incoming (09:26:45) and first PRESENTED (09:27:31) matches “bell / request arrived but pay sheet not auto-opened; had to open manually.”

Bitkit Version

Mainnet debug 2.5.0 (190), master @ dbbf90f02

Device / OS

Samsung Galaxy S22 (SM-S901B), Android 16

Reproducibility

Often (>50%) — seen on this canary run; layout always scrollable into a bad state once on the sheet.

Additional context

• Fresh wallet (not the restored The Piotr identity from [Bug]: Shop Paykit request never arrives after restore; Encrypted Link stuck in recovery_required #1402).
• On-chain private Paykit to Shop seller; order c62d186d; amount ₿1,753; sent ₿1,894 incl. fee.
• UI language Polish (Przesuń, aby zapłacić).
• Auto-open may be intentional notify-only today — call out expected product behaviour if so.