Changelog

odoo/o-spreadsheet#8110

Created by BI, Vincent Schippefilt (vsc)

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- legal/cla: (runtime 16s)

label: odoo:master-file-manager-demo-vsc
head: 9cf549028937dbc9afc1ad48b710e826367d761d

	odoo/o-spreadsheet
master	#8110 ^{missing statuses} ^{missing r+}

[ADD] demo: local file manager with IndexedDB storage

Adds a file manager demo page (demo/files.html + demo/files.js) that stores spreadsheet files locally in IndexedDB. Features include:
- Sidebar file list with create, rename, delete, and switch
- Per-file revision counter and last-modified tooltip
- Import/export individual files as XLSX or OSHEET JSON
- Backup the entire database to a single .ofiles-backup.json file
- Restore all files from a backup (replaces current DB contents)

task-0