feat: add automated konsolerc geometry sanitization and git backup integration

- Implement [MainWindow] section stripping in backup and restore scripts
  to prevent screen geometry/monitor layout noise across devices
- Add robust hostname detection and customizable archive naming in backup.sh
- Add optional interactive git commit and push prompt upon successful backup
- Update restore.sh diff preview and extraction to respect sanitized konsolerc
- Add AGENTS.md documentation detailing script architecture and conventions

AGENTS.md

@@ -0,0 +1,31 @@
+# AGENTS.md
+
+## Overview
+Lightweight Bash utility scripts for KDE Konsole configuration backup, cross-device synchronization, and restoration.
+
+## Key Features & Commands
+
+- **Backup**: `./backup.sh`
+  - Automatically strips device-specific screen geometry / monitor layouts (`[MainWindow]` section in `konsolerc`) to ensure clean cross-device sync.
+  - Staged in `backups/` with default naming format: `konsole_backup_<hostname>_YYYYMMDD_HHMMSS.zip`.
+  - Prompts user to confirm or edit the backup archive filename before saving.
+  - Enforces a retention policy of max 10 backups (older ones deleted and removed via `git rm` if inside a git repository).
+  - Prompts to commit and push the new backup to git remote.
+
+- **Restore**: `./restore.sh [optional_zip_path]`
+  - Supports positional arguments, stdin piping (`echo "file.zip" | ./restore.sh`), and an interactive selection menu if no input is provided.
+  - Sanitizes `konsolerc` to avoid overwriting the target machine's window/screen geometry.
+  - Supports file-by-file diff preview (`[d]`) using `git diff --no-index` or `diff`.
+  - Reads interactive prompts safely from `/dev/tty` when stdin is redirected.
+
+## Target Paths (Relative to `$HOME`)
+- `.config/konsolerc` (sanitized of `[MainWindow]` geometry)
+- `.local/share/konsole` (profiles, color schemes, bookmarks, keytabs)
+- `.local/share/kxmlgui5/konsole` (UI toolbars / actions)
+- `.config/konsole.notifyrc`
+- `.config/konsolesshconfig`
+
+## Implementation Details & Conventions
+- **Shell**: Pure Bash 4+ with `set -euo pipefail`.
+- **Safety**: Uses `mktemp -d` for temporary staging directories with `trap ... EXIT` cleanup.
+- **Verification**: Run `bash -n backup.sh restore.sh` to check syntax.