unused messages lix validation validation rule

[samuelstroschein]

Discussed in opral/monorepo#1961

^{Originally posted by samuelstroschein January 2, 2024}

Context

Over time messages became stale and are not used in source code anymore. No mechanism exists at the moment that "lints" unused messages that can safely be deleted. The result is an evergrowing amount of messages that translators are supposed to translate even though some or many messages aren't used.

Proposal

Introduce an "unused message" lint rule.

The lint rule parses the source code and searches for message references (similar/identical to the ide extensions message reference matchers)

Requirements

opral/monorepo#2126

[linear]

MESDK-41 unused messages lint rule

[samuelstroschein]

Someone on discord found a neat workaround for paraglide js by using https://knip.dev/. See https://discord.com/channels/897438559458430986/1283048712448376873/1283157547909517362