feat(release): RELEASE identity + image tag single-sourcing (#10)

- RELEASE file: single source of release version (0.0.X until declared stable)
- common.sh load_release(): validates version, derives
  MOSAIC_IMAGE_TAG=mosaic-poc-agent:<pi>-r<release> from the pinned pi dep
- compose.yaml: image tag is required env; build/hello/verify call load_release
- verify.sh derives the image name instead of hardcoding it
- package.json version aligned to the same 0.0.X line

Closes #10

scripts/build.sh

@@ -6,6 +6,7 @@ cd "$(dirname "$0")/.."
 source scripts/common.sh
 
 load_config
+load_release
 
 bootstrap_runtime_dir
 

scripts/common.sh

@@ -19,6 +19,21 @@ load_config() {
     MOSAIC_DEV_DIR="$MOSAIC_DATA_ROOT"
 }
 
+# Resolve the release identity: RELEASE is the single source of the
+# release version (stays 0.0.X until declared stable); the image tag
+# derives from it plus the pinned pi dependency version.
+load_release() {
+    local release pi_version
+    release="$(tr -d '[:space:]' < RELEASE)"
+    if ! printf '%s' "$release" | grep -Eq '^[0-9]+\.[0-9]+\.[0-9]+$'; then
+        echo "common: RELEASE must be a semver-ish version, got: '$release'" >&2
+        exit 1
+    fi
+    pi_version="$(node -p "require('./package.json').dependencies['@earendil-works/pi-coding-agent']")"
+    export MOSAIC_RELEASE="$release"
+    export MOSAIC_IMAGE_TAG="mosaic-poc-agent:${pi_version}-r${release}"
+}
+
 # Ensure the configured runtime data directory exists and carries this
 # project's ownership marker. The marker is what scripts/reset.sh requires
 # before it will delete anything.

scripts/hello.sh

@@ -11,6 +11,7 @@ cd "$(dirname "$0")/.."
 source scripts/common.sh
 
 load_config
+load_release
 
 bootstrap_runtime_dir
 

scripts/verify.sh

@@ -14,10 +14,11 @@ cd "$(dirname "$0")/.."
 # shellcheck source=common.sh
 source scripts/common.sh
 
-IMAGE="mosaic-poc-agent:0.84.4"
 EXPECTED="${EXPECTED_MARKER:-MOSAIC_HELLO_OK}"
 
 load_config
+load_release
+IMAGE="$MOSAIC_IMAGE_TAG"
 
 # Ensure the configured data root exists (host-owned) before the mount,
 # otherwise Docker would auto-create a root-owned directory.