Document design choices and standardize Dockerfile

scripts/build-linux.sh

@@ -1,13 +1,22 @@
 #!/usr/bin/env bash
 set -euo pipefail
 
+# Optional first argument lets a developer or CI job choose the output path.
+# dist/linux/pysentry is the default so generated binaries stay outside src/.
 output="${1:-dist/linux/pysentry}"
 mkdir -p "$(dirname "$output")"
 
+# Fyne needs CGO for its native desktop backend. The script pins the target to
+# linux/amd64 because this is the first supported Linux artifact; other
+# architectures can be added later as explicit build targets.
 export CGO_ENABLED=1
 export GOOS=linux
 export GOARCH=amd64
 
+# -trimpath removes local machine paths from debug/build metadata. -s -w strips
+# symbol/debug tables to keep the desktop binary smaller.
 go build -trimpath -ldflags "-s -w" -o "$output" ./cmd/pysentry
 
+# The application icon is embedded by Go, so the Linux build does not need a
+# sidecar assets directory beside the executable.
 echo "Built $output"