feat: render notifications with compact style

[timothyckl]

Renders patch.nvim notifications as single-line compact boxes and removes the duplicated plugin name from each message.

• patch.ui.notify.send now defaults every notification to render = "compact" (still overridable by callers; ignored by the vim.notify fallback).
• Dropped the redundant "patch: " prefix from the workflow notification helpers, since the patch.nvim title already identifies the plugin. Messages now read like "patch.nvim: no selection found" instead of "patch.nvim: patch: no selection found".
• Updated the options assertions in test_notify.lua and the message expectations in test_workflow.lua to match.

[timothyckl]

yipee