internet-speed-meter@mebs: Add new applet

[MDHasan0078]

A lightweight Cinnamon applet that displays real-time internet upload and download speed in the panel.

Features

• Real-time download/upload speed (auto-scaling units: B/s, KB/s, MB/s, GB/s or bit variants)
• Automatic interface detection via the default route (no external commands spawned)
• Compact single-line or stacked layout
• Configurable refresh interval, decimal places, and font size

Implementation notes

• Reads rx_bytes/tx_bytes from /sys/class/net/<iface>/statistics/
• Uses only Mainloop.timeout_add + file reads per tick (no subprocesses, no watchdog warnings)
• GPL-3.0

[github-actions]

Best-practices scanner

This is a regex-based check for API usage that can pose security, performance or
maintainability issues, or that may already be provided by Cinnamon. Most findings
are advisory and do not automatically disqualify a pull request.

This check is not perfect and will not replace a normal review.

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Found 2 potential issue(s):

⚠️ WARNING

⚠️ sync_file_get_contents

internet-speed-meter@mebs/files/internet-speed-meter@mebs/applet.js:43

let [, content] = GLib.file_get_contents("/proc/net/route");

Synchronous file_get_contents() blocks the main loop.
Use Gio.File.load_contents_async() instead.

internet-speed-meter@mebs/files/internet-speed-meter@mebs/applet.js:60

let [, content] = GLib.file_get_contents(path);

Synchronous file_get_contents() blocks the main loop.
Use Gio.File.load_contents_async() instead.

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Automated pattern check.

[MDHasan0078]

Fixed the two best-practices scanner findings. Replaced both synchronous GLib.file_get_contents() calls with async Gio.File.load_contents_async():

• Interface detection now reads /proc/net/route asynchronously (with a _detecting guard so retries don't stack).
• Speed sampling now chains async reads per tick (rx_bytes \u2192 tx_bytes \u2192 compute) with a _sampling guard to prevent overlapping samples.

Verified live after reload: label updates correctly (\u2193 49.0 KB/s \u2191 6.3 KB/s \u2192 \u2193 2.4 KB/s \u2191 2.4 KB/s), no new warnings in ~/.xsession-errors.