feat: add arm and 32 bit builds

[elibosley]

Summary by CodeRabbit

• New Features
  • Added pre-built release binaries for additional platforms: 32-bit Linux, ARM-based Linux, 32-bit Windows, and FreeBSD (x86-64 and ARM64 architectures).

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[coderabbitai]

📝 Walkthrough

Walkthrough

The pull request expands CI/CD workflows to support additional platform targets (linux/386, linux/arm, windows/386, freebsd/amd64, freebsd/arm64) by updating build matrices and introducing dynamic output naming conventions for ARM-specific versioning. README documentation is updated to reflect the new pre-built release assets.

Changes

Cohort / File(s)	Summary
CI/CD Workflow Configuration .github/workflows/parity.yml, .github/workflows/release.yml	Expanded build matrix with 5 additional GOOS/GOARCH targets. Introduced dynamic OUTPUT_NAME variable to handle ARM-specific naming (e.g., apprise-go-${GOOS}-${GOARCH}v${GOARM}${EXT}). Replaced static file references with computed paths using ${OUTPUT_NAME} throughout build, sign, zip, and release steps.
Documentation README.md	Added 5 new pre-built release asset entries to the Releases section: apprise-go-linux-386, apprise-go-linux-armv7, apprise-go-windows-386.exe, apprise-go-freebsd-amd64, apprise-go-freebsd-arm64.

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~10 minutes

Poem

🐰 Whiskers twitching with delight
More platforms hop into the light!
From ARM to 386 we run,
FreeBSD joins our building fun—
Dynamic names keep all in sight! 🚀

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