feat(console): parameter builder in the command explorer (phase 3)

The detail pane's Parameters section is now an editable form: each parameter is
a type-hinted input field (string / number / json, optional marked), and a live
"Builds" preview shows the command being assembled. String values are
auto-quoted; a required field left empty keeps its placeholder and disables
"Insert & run"; trailing empty optionals are omitted.

Insert and Insert & run now use the assembled command (not just the template),
so Insert & run works for parameterized commands once the required fields are
filled — destructive commands still confirm first. Param fields reset when the
selected command changes or the modal opens. Keyboard nav (Up/Down/Enter) is
scoped to the search box so typing in a field doesn't move the selection.

A best-effort parseParamSpecs turns the human-readable param templates into
fields; JSON-array params (z_sendmany, createrawtransaction) surface as a single
"json" field the user pastes into. Adds the console_ref_builds label + 8
translations.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/util/i18n.cpp

@@ -1306,6 +1306,7 @@ void I18n::loadBuiltinEnglish()
         strings_["console_ref_no_params"] = "Takes no parameters.";
         strings_["console_ref_optional"] = "optional";
         strings_["console_ref_example"] = "Example";
+        strings_["console_ref_builds"] = "Builds";
         strings_["console_ref_destructive"] = "Consequential";
         strings_["console_ref_run_confirm"] = "Run %s now? This is a consequential command.";
         strings_["console_ref_cancel"] = "Cancel";