feat(console): right-click "Copy value" for hashes/addresses under the cursor

Right-clicking the output now offers "Copy <value>" when a long alphanumeric token
(txid/blockhash/address, >=16 chars) is under the cursor — resolved via screenToTextPos.
Uses right-click so it never conflicts with the left-drag text selection.

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

src/util/i18n.cpp

@@ -983,6 +983,7 @@ void I18n::loadBuiltinEnglish()
         strings_["console_help_stop"] = "  stop          - Stop the daemon";
         strings_["console_line_count"] = "%zu lines";
         strings_["console_matches"] = "matches";
+        strings_["console_copy_value"] = "Copy";
         strings_["console_new_lines"] = "%d new lines";
         strings_["console_no_daemon"] = "No daemon";
         strings_["console_not_connected"] = "Error: Not connected to daemon";