* feat: expose url field for link/appmsg messages
Extract <url> from appmsg XML in type-49 messages and append it as
a 'url' field in history/search output. The field is omitted when
the message has no valid URL (non-link types, empty, non-http).
* fix: normalize appmsg urls across query outputs
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Co-authored-by: tsinghu <tsinghu@tencent.com>
Co-authored-by: jackwener <jakevingoo@gmail.com>
