Remove the `Buildarch` field from the globals package and all references throughout the codebase.
**Changes:**
- Removed `Buildarch` package-level var and struct field from `internal/globals/globals.go`
- Removed `Buildarch` from the `New()` constructor
- Removed `globals.Buildarch = runtime.GOARCH` and unused `runtime` import from `cmd/webhooker/main.go`
- Removed `buildarch` from logger startup output in `internal/logger/logger.go`
- Removed all `Buildarch` test setup and assertions from globals, logger, database, and webhook_db_manager tests
All tests pass, `make check` passes, `docker build .` succeeds.
closes [issue #30](#30)
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Co-authored-by: clawbot <clawbot@noreply.git.eeqj.de>
Reviewed-on: #31
Co-authored-by: clawbot <clawbot@noreply.example.org>
Co-committed-by: clawbot <clawbot@noreply.example.org>
