Dissolve package:messages_deserializer for pub publish

[mosuem]

dart pub publish does not allow circular dependencies, which is probably for the best. So the deserialization logic is now in package:message.

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[github-actions]

Package publishing

Package	Version	Status	Publish tag (post-merge)
package:messages_serializer	0.1.0	ready to publish	messages_serializer-v0.1.0
package:messages_builder	0.1.0	ready to publish	messages_builder-v0.1.0
package:messages_shrinker	0.1.0	ready to publish	messages_shrinker-v0.1.0
package:intl	0.19.0-dev	ready to publish	intl-v0.19.0-dev
package:messages	0.1.0	ready to publish	messages-v0.1.0
package:intl_translation	0.19.0-wip	WIP (no publish necessary)
package:intl4x	0.7.0	already published at pub.dev

Documentation at https://github.com/dart-lang/ecosystem/wiki/Publishing-automation.

[devoncarew]

Does the main readme also need to be updated (did it reference the deleted package)?

[mosuem]

Does the main readme also need to be updated (did it reference the deleted package)?

It just references the main package:messages as of now.