feat: unify release steps

packages/release/release.nix

@@ -1,13 +1,11 @@
 # release.nix
 {
   pkgs,
-  # Source of truth is always $ROOT_DIR/VERSION.
-  # Format:
-  #   line 1: X.Y.Z
-  #   line 2: CHANNEL (stable|alpha|beta|rc|internal|...)
-  #   line 3: N (prerelease number, 0 for stable)
   postVersion ? "",
-  versionFiles ? [ ],
+  release ? [ ],
+  # Unified list, processed in declaration order:
+  #   { file = "path/to/file"; content = "..."; }   — write file
+  #   { run = "shell snippet..."; }                  — run script
   channels ? [
     "alpha"
     "beta"
@@ -19,24 +17,28 @@
 let
   channelList = pkgs.lib.concatStringsSep " " channels;
 
-  versionFilesScript = pkgs.lib.concatMapStrings (f: ''
-    mkdir -p "$(dirname "${f.path}")"
-    ${f.content} > "${f.path}"
-    log "Generated version file: ${f.path}"
-  '') versionFiles;
+  releaseScript = pkgs.lib.concatMapStrings (
+    entry:
+    if entry ? file then
+      ''
+        mkdir -p "$(dirname "${entry.file}")"
+        cat > "${entry.file}" << NIXEOF
+        ${entry.content}
+        NIXEOF
+        log "Generated version file: ${entry.file}"
+      ''
+    else if entry ? run then
+      ''
+        ${entry.run}
+      ''
+    else
+      builtins.throw "release entry must have either 'file' or 'run'"
+  ) release;
 
   script =
     builtins.replaceStrings
-      [
-        "__CHANNEL_LIST__"
-        "__VERSION_FILES__"
-        "__POST_VERSION__"
-      ]
-      [
-        channelList
-        versionFilesScript
-        postVersion
-      ]
+      [ "__CHANNEL_LIST__" "__RELEASE_STEPS__" "__POST_VERSION__" ]
+      [ channelList releaseScript postVersion ]
       (builtins.readFile ./release.sh);
 in
 pkgs.writeShellApplication {