[Code scan] Handle missing or invalid custom template files

[njzjz]

This issue was found during a Codex global code scan of the repository.

Baseline commit: e3c5b38

Problem

The custom template import path assumes a file is selected and that its contents are valid JSON. Both reader.readAsText(this.file[0]) and JSON.parse(e.target.result) are unguarded.

Code references:

dpgui/src/views/NewConfig.vue

Lines 30 to 49 in e3c5b38

	add: function () {
	const name = this.name;
	const that = this;
	const reader = new FileReader();
	reader.onload = function (e) {
	const hash = require("crypto")
	.createHash("sha256")
	.update(e.target.result)
	.digest("hex");
	const obj = JSON.parse(e.target.result);
	const curr = that.$storage.getStorageSync("CustomTemplate") || {};
	curr[hash] = {
	name: name,
	obj: obj,
	};
	that.$storage.setStorageSync("CustomTemplate", curr);
	that.$router.push("/input");
	that.$root.$app.update_navi();
	};
	reader.readAsText(this.file[0]);

Relevant snippet:

const obj = JSON.parse(e.target.result);

reader.readAsText(this.file[0]);

Impact

Clicking Add without selecting a file, or selecting malformed JSON, throws an uncaught browser error instead of giving a recoverable UI error.

Suggested fix

Disable Add until a file is selected, wrap JSON parsing in try/catch, handle FileReader.onerror, and show a validation message instead of navigating away.