fix(wdk, dapp-client): fix cron lastRun persistence and disambiguate redirect payloads

[Ysh204]

Problem

This PR resolves two key issues:

1. WDK Cron Job Last Run Persistence: On page reloads, cron job lastRun timestamps were overwritten to 0 in localStorage, leading to background jobs running too frequently.
2. Redirect Payload UTF-8/Latin-1 Disambiguation: Redirect payload decoding used a try-catch pattern to auto-detect UTF-8. Legacy Latin-1 payloads with specific byte patterns (e.g., é) were incorrectly parsed as valid UTF-8 sequences (é), corrupting the data.

Solution

1. WDK Cron: Updated the job checking loop to initialize in-memory lastRun times with the persisted value loaded from storage prior to running checks. This prevents overwriting the stored value with 0 when a job does not execute.
2. Disambiguation: Added an explicit encoding=utf-8 search parameter to redirect request and response URLs. The client now decodes using UTF-8 only when the encoding=utf-8 parameter is present, otherwise safely falling back to Latin-1.

Verification

• Added a full unit test suite for WDK cron job persistence in packages/wallet/wdk/test/cron.test.ts.
• Updated existing tests and added a specific collision test case in packages/wallet/dapp-client/test/DappTransport.test.ts using legacy payload text é to ensure no regression occurs.
• Both test suites compile, build, and pass successfully.