A Source-Approval Surface in Memopop Native — Curation Before the Run, Not After
Adds an `approving_sources` stage to the native app's flow machine, between defining the deal and generating the memo, plus the surface that fills it: approve / deny-with-reason / re-search / preview / add-by-paste, backed by SearXNG candidate discovery. Curation is frontloaded because a memo written against an unconstrained corpus cannot be fixed by approving sources afterwards. Also wires six new routes through the Rust dispatcher, which is an allowlist — new sidecar endpoints are invisible to the webview until they are added to it.