Improve Build Scripts & Build‑Type Workflow

[ZFordDev]

Summary

The current build scripts have been cleaned as part of #120, but they still reflect a minimal workflow. SnapDock would benefit from a more structured build‑type system (dev, test, release, store) and automated metadata injection.

This issue tracks the next evolution of the build pipeline.

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Problem

The existing scripts are functional but limited:

• No build‑type flags (dev/test/release/store)
• No automated metadata injection (stage/date)
• No signing workflow
• No platform‑specific clarity
• No CI‑aware build modes
• No separation between “pack”, “build”, and “release” semantics

These limitations are outside the scope of #120, but should be addressed in a future milestone.

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Goals

• Introduce build‑type commands (e.g., build:dev, build:release)
• Auto‑generate metadata (stage + date) during build
• Add signing workflow for Windows/macOS
• Add CI‑aware build modes
• Remove the need for manual metadata in package.json
• Improve clarity and maintainability of the scripts block

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Non‑Goals

• No changes to artifact naming (already completed)
• No changes to platform overrides
• No changes to publish config
• No changes to build.js beyond metadata injection

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Notes

This issue is intentionally separate from #120 to keep the parent milestone focused and clean.
The current scripts are stable and correct, but not yet “final form”.