feat: QRコード経由のインポートを実装

[nandenjin]

出力される収支計算書にコンテンツをシリアライズしたQRコードを付し、PDFや印刷済みのデータからsawaganiへの再インポート・編集が可能なようにします。

収支計算書をsawaganiから出力するにあたり、現在は一度出力した内容を修正するのは困難であるという問題があります（sawagani上で入力する表紙の項目は、元データのスプレッドシートから復元できないため）。この機能により、sawaganiは帳票をすぐにでも提出できる状態を保持したまま、一度出力した内容を何度でも再編集できる自由を得ることになります。

[Copilot]

Pull Request Overview

This PR implements QR code-based data import functionality for sawagani, allowing users to re-import and re-edit financial statements that have been previously exported as PDFs. The feature addresses the limitation where once a financial statement is exported, it becomes difficult to modify the cover page information that was entered in sawagani.

Key changes include:

• Implementation of QR code generation and scanning for data serialization
• Addition of PDF import capability alongside existing CSV import
• Refactoring of serialization logic to use JSONCrush compression instead of base64 encoding

Reviewed Changes

Copilot reviewed 18 out of 20 changed files in this pull request and generated 8 comments.

Show a summary per file

File	Description
src/store/data.ts	Adds SerializedData type and refactors serialization methods with version tracking
src/lib/serialization.ts	New serialization utility using JSONCrush with base64 fallback
src/lib/importer/pdf.ts	Complex PDF QR code scanning implementation with image processing
src/lib/importer/index.ts	Unified import interface supporting both CSV and PDF files
src/components/RestoreInfo.vue	QR code display component for PDF export pages
src/components/ImporterDialog.vue	File import dialog with drag-and-drop support
src/index.ts	Updates URL hash handling to use new serialization format
package.json	Dependency updates and new QR code related libraries

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[Copilot]

Pull Request Overview

Copilot reviewed 13 out of 14 changed files in this pull request and generated 4 comments.

---

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[Copilot]

The magic numbers 64 (buffer size) and 200 (threshold) should be defined as named constants with documentation explaining their purpose and how they were determined.

Suggested change

	* 画像データを黒い部分に応じて縦横のグリッドで分割する
	* @param data
	* @param bufferSize 検出に使う縮小画像のサイズ
	* @returns グリッド領域の配列
	*/
	function getContentGrid(
	data: ImageData,
	bufferSize = 64,
	threshold = 200,
	* Default buffer size for image downsampling when detecting grid areas.
	* This value was chosen to balance performance and accuracy for typical scanned document images.
	* Adjust if input images are much larger or smaller.
	*/
	const DEFAULT_BUFFER_SIZE = 64;
	/**
	* Threshold for detecting dark regions in the image.
	* Pixels with intensity below this value are considered "black".
	* Determined empirically for common document scans; adjust for different lighting or image types.
	*/
	const DEFAULT_THRESHOLD = 200;
	/**
	* 画像データを黒い部分に応じて縦横のグリッドで分割する
	* @param data
	* @param bufferSize 検出に使う縮小画像のサイズ
	* @param threshold 黒判定の閾値
	* @returns グリッド領域の配列
	*/
	function getContentGrid(
	data: ImageData,
	bufferSize = DEFAULT_BUFFER_SIZE,
	threshold = DEFAULT_THRESHOLD,

[Copilot]

The magic number 300 for chunk size should be defined as a named constant with documentation explaining why this specific value was chosen for QR code data chunking.

Suggested change

	const chunkSize = 300
	/**
	* The maximum number of characters per QR code chunk.
	* Chosen as 300 to ensure that the encoded data fits within a QR code of size 150x150 at error correction level 'L',
	* and remains reliably scannable across devices. Adjust if QR code capacity or reliability requirements change.
	*/
	const QR_CODE_CHUNK_SIZE = 300
	const chunkSize = QR_CODE_CHUNK_SIZE

[Copilot]

The Promise doesn't handle FileReader errors. Add an error event listener to reject the promise when file reading fails.

Suggested change

	new Promise((resolve) => {
	const reader = new FileReader()
	reader.addEventListener('load', (e) => {
	const text = e.target?.result as string
	const { data } = parseCSV<string[]>(text)
	resolve(data)
	})
	new Promise((resolve, reject) => {
	const reader = new FileReader()
	reader.addEventListener('load', (e) => {
	const text = e.target?.result as string
	const { data } = parseCSV<string[]>(text)
	resolve(data)
	})
	reader.addEventListener('error', (e) => {
	reject(e)
	})