fix: a send the confirmation screen refuses moves nothing on it (closes #583)

Sign & Send wrote its two refusals, a network changed since review and a fee over the bound, into the errors box above the password field. That box reserves one empty line, so a refusal grew it and pushed the password field and Sign & Send down.

Each refusal now has its own box with its sentence fixed in index.html, holding its space from the first paint and only made visible, as #558 did for the balance messages. The fee refusal no longer quotes the fee; its full reason is logged. A Chrome test raises the stub node's fee only at signing and checks the password field and Sign & Send stay where they were.

Model: opus-5-5

tests/confirmTxFeeBound.test.js

@@ -12,7 +12,7 @@
 // The check is driven here with a fake connected signer rather than a real
 // one: populateTransaction() returns the fees the node would have produced,
 // and sendTransaction() records whether the send actually happened. The real
-// DOM path around it — reading the fee error into the reserved errors box — is
+// DOM path around it — the refusal shown in the box reserved for it — is
 // covered by the Chrome e2e suite.
 
 globalThis.chrome = {