Add wallet connection stall detection and ad-blocker hint

[sochima2]

Motivation

• Wallet extension scripts can be silently blocked by ad blockers causing useConnect/reconnect flows to hang with no error, leading to confused users and support requests.
• Introduce a targeted detection and message to surface when a wallet attempt has stalled so users are prompted to disable ad blockers for the site.

Description

• Add useWalletConnectionStallDetection hook in src/hooks/useWalletConnectionStallDetection.ts with a named timeout constant WALLET_CONNECTION_STALL_TIMEOUT_MS and shared message WALLET_CONNECTION_AD_BLOCKER_MESSAGE.
• Wire the hook into ConnectWalletButton and WalletConnectCalloutBanner so the ad-blocker suggestion appears only when a wallet connection/reconnect remains pending past the timeout and is cleared when the attempt succeeds or fails.
• Add unit tests in src/hooks/__tests__/useWalletConnectionStallDetection.test.ts covering the stalled, success-before-timeout, and failure-before-timeout behaviors.

Testing

• Ran pnpm exec vitest run src/hooks/__tests__/useWalletConnectionStallDetection.test.ts, and the new tests passed.
• Ran pnpm lint and pnpm build, both completed successfully.
• A broader pnpm test invocation that ran the full suite surfaced pre-existing unrelated failures (missing test deps and unrelated assertions) which are not caused by this change.

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Codex Task