Updating DDC's bootstrapper for auto hot reload/restart.

[Markzipan]

Synchronizes some logic with that of the rest of our ecosystem.

[github-actions]

Package publishing

Package	Version	Status	Publish tag (post-merge)
package:build	4.0.3	already published at pub.dev
package:build_config	1.2.0	already published at pub.dev
package:build_daemon	4.1.1	already published at pub.dev
package:build_modules	5.1.4	already published at pub.dev
package:build_runner	2.11.0-wip	WIP (no publish necessary)
package:build_test	3.5.5-wip	WIP (no publish necessary)
package:build_web_compilers	4.4.5	ready to publish	build_web_compilers-v4.4.5
package:scratch_space	1.2.0	already published at pub.dev

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

[github-actions]

PR Health

Changelog Entry ✔️

Package	Changed Files

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[davidmorgan]

Looks good--if you wanted to release, please feel free to go ahead and hit the button after you merge. Thanks!