Add Reset all data to Settings > Data and release 1.2.0

Reset all data stages a wipe behind a typed RESET confirmation and applies it
on the next start, before the database is opened. It deletes the database,
assets, PDF archive, imported fonts and every backup, then the setup wizard
shows again.

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

README.md

@@ -8,7 +8,7 @@ connection. The only optional network feature is the ERPNext push, which you con
 
 Targets: Void Linux (xbps, WebKitGTK 2.50 or newer) and Windows 10/11 (NSIS installer, WebView2).
 
-Current release: **1.1.0**. Installers and the Void package are attached to the release on the project's Gitea
+Current release: **1.2.0**. Installers and the Void package are attached to the release on the project's Gitea
 page (see "Installing").
 
 ## Features
@@ -38,6 +38,7 @@ page (see "Installing").
 - **Payments.** Record payments against an issued invoice, including TDS deducted by the client. Outstanding
   balance is cash plus TDS against the invoice total.
 - **History.** Filterable invoice list, detail view with payments, and CSV or JSON export of the list.
+- **Reset all data.** Settings, Data wipes everything and returns to first-run setup after a typed `RESET`.
 - **Backup and restore.** Manual and automatic daily backups of the database, assets, PDF archive and imported fonts.
 - **Export for other software.** `voiced.invoice.v1` JSON and line-item CSV for selected invoices
   (see `docs/voiced-invoice-v1.md`).
@@ -85,11 +86,11 @@ The release procedure, including the manual first-run checklist, is in `docs/REL
 ## Installing
 
 Download the files for your platform from the release page of the project on `git.bongbetic.com` (Releases, then
-`v1.1.0`).
+`v1.2.0`).
 
-- **Windows 10/11:** run `Voiced_1.1.0_x64-setup.exe`. It is a per-user install and is not code-signed, so Windows
+- **Windows 10/11:** run `Voiced_1.2.0_x64-setup.exe`. It is a per-user install and is not code-signed, so Windows
   SmartScreen may warn: choose "More info", then "Run anyway".
-- **Void Linux:** install `voiced-1.1.0_1.x86_64.xbps` from a local repository (see "Installing on Void Linux").
+- **Void Linux:** install `voiced-1.2.0_1.x86_64.xbps` from a local repository (see "Installing on Void Linux").
 
 On first launch the setup wizard asks for your business details, logo, bank account and invoice numbering. Nothing is
 pre-filled. Uninstalling does not delete your data (see "Where data lives"); to start from scratch use
@@ -126,6 +127,16 @@ Settings, Data tab.
   backup files on storage you trust, do not email or upload them casually, and rotate the ERPNext API key if a
   backup is lost.
 
+## Reset all data
+
+Settings, Data, Reset all data. This permanently deletes the database (invoices, clients, payments, business details
+and settings), `assets/`, the PDF `archive/`, imported `fonts/` and the whole `backups/` folder, including automatic
+backups and the `pre-restore-*` safety copies, then starts Voiced as if it were new (the setup wizard shows again).
+You must type `RESET` to enable the button. The wipe is staged and applied on the next start, before the database is
+opened, so the "Delete everything and restart" button restarts the app for you; if a file cannot be deleted the
+wipe is retried on the next start. Backup zips you saved elsewhere are not touched. Take a backup first if you may
+want the data back.
+
 ## Fonts and licences
 
 Eleven families are bundled as static TTF files in `public/fonts/<family>/`, each with its `OFL.txt`: DM Sans,