[register_devices] Support comment lines #30127

Right now, register_devices expects devices_file to contain only the header row and valid device rows.

Any blank line or comment causes the action to fail. It would be nice to allow lightweight annotations in the file, so larger device lists are easier to organize and maintain.

Idea

Support #-prefixed comment lines (and blank lines) in devices_file, ignored before the device rows are parsed.

Backwards compatibility

Files without comments or blank lines would keep working exactly as they do today.

Example

Device ID	Device Name	Device Platform

# QA team
A123456789012345678901234567890123456789	QA iPhone 1	ios
B123456789012345678901234567890123456789	QA iPhone 2	ios

# Design team
C123456789012345678901234567890123456789	Design iPad	ios

# Temporarily disabled
# D123456789012345678901234567890123456789	Old contractor device	ios

Why this could help

• Grouping devices into sections (team, project, etc.)
• Temporarily disabling an entry by commenting it out, without losing the line
• Leaving a short note about a device