fix(packaging): omit Homebrew sample config

[corylanou]

Description

Stop the Homebrew formula from installing the sample configuration into Homebrew's prefix. Homebrew installations now install only the Litestream binary, while release archives and Debian/RPM packages retain their existing configuration behavior.

Motivation and Context

Homebrew installs configuration files under its own prefix, such as /opt/homebrew/etc, while Litestream defaults to /etc/litestream.yml. The installed sample was therefore never discovered automatically, leaving users with an unused file while the CLI referenced a different location.

Fixes #1412

How Has This Been Tested?

• pre-commit run --all-files
• go test -race -v ./...
• git diff --check origin/main...HEAD

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (would cause existing functionality to not work as expected)

Checklist

• My code follows the code style of this project (go fmt, go vet)
• I have tested my changes (go test ./...)
• I have updated the documentation accordingly (no documentation change is needed for this packaging-only fix)

[github-actions]

PR Build Metrics

✅ All clear — no issues detected

Check	Status	Summary
Binary size	✅	37.10 MB (0.0 KB / 0.00%)
Dependencies	✅	No changes
Vulnerabilities	✅	None detected
Go toolchain	✅	1.25.13 (latest)
Module graph	✅	1240 edges (0)

Binary Size

	Size	Change
Base (534d8fb)	37.10 MB
PR (d1dbb0e)	37.10 MB	0.0 KB (0.00%)

Dependency Changes

No dependency changes.

govulncheck Output

=== Symbol Results ===

No vulnerabilities found.

Your code is affected by 0 vulnerabilities.
This scan also found 1 vulnerability in packages you import and 3
vulnerabilities in modules you require, but your code doesn't appear to call
these vulnerabilities.
Use '-show verbose' for more details.

Build Info

Metric	Value
Build time	44s
Go version	go1.25.13
Commit	d1dbb0e

History (1 previous)

Commit	Updated	Status	Summary
65cda2a	2026-08-18 15:59 UTC	✅	37.09 MB (0.0 KB / 0.00%)

---

_{🤖 Updated on each push.}