Revert to Semantic Versioning and Setup Release-Please

[vuon9]

I have reverted the versioning scheme to Semantic Versioning as requested. This involved resetting the version in build/config.yml to 0.9.4 (preparing for a 0.10.0 release) and setting up release-please for automated versioning and releases, similar to the youtube-listen-mode repository. I've also updated the GitHub Actions release workflow to integrate with release-please.

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PR created automatically by Jules for task 10856427276505998036 started by @vuon9

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[github-actions]

Package	Line Rate	Health
devtoolbox/internal/barcode	90%	✔
devtoolbox/internal/codeformatter	78%	➖
devtoolbox/internal/converter	60%	➖
devtoolbox/internal/datagenerator	91%	✔
devtoolbox/internal/datetimeconverter	73%	➖
devtoolbox/internal/jwt	42%	❌
devtoolbox/internal/settings	0%	❌
Summary	68% (3504 / 5175)	➖

Minimum allowed line rate is 60%