chore: Add v26 deprecation warning about implicit publishing in CI (#9475)

Author: biw

.changeset/pretty-hats-appear.md

@@ -0,0 +1,5 @@
+---
+"app-builder-lib": patch
+---
+
+deprecate: warn about implicit publishing in CI

.context/notes.md

@@ -86,14 +86,15 @@ export class PublishManager implements PublishContext {
     if (!isPullRequest() || forcePublishForPr) {
       if (publishOptions.publish === undefined) {
         if (process.env.npm_lifecycle_event === "release") {
+          log.warn("Implicit publishing triggered by npm lifecycle event 'release'. This behavior will be disabled in electron-builder v27. Please use --publish explicitly.")
           publishOptions.publish = "always"
         } else {
           const tag = getCiTag()
           if (tag != null) {
-            log.info({ reason: "tag is defined", tag }, "artifacts will be published")
+            log.warn({ tag }, "Implicit publishing triggered by git tag. This behavior will be disabled in electron-builder v27. Please use --publish explicitly.")
             publishOptions.publish = "onTag"
           } else if (isCI) {
-            log.info({ reason: "CI detected" }, "artifacts will be published if draft release exists")
+            log.warn("Implicit publishing triggered by CI detection. This behavior will be disabled in electron-builder v27. Please use --publish explicitly.")
             publishOptions.publish = "onTagOrDraft"
           }
         }

packages/app-builder-lib/src/publish/PublishManager.ts

@@ -17,6 +17,17 @@ If `GITHUB_RELEASE_TOKEN` is defined, it will be used instead of (`GH_TOKEN` or
 - you could make your `GITHUB_TOKEN` "Read-only" when creating a fine-grained personal access token, and "Read and write" for the `GITHUB_RELEASE_TOKEN`.
 - "Contents" fine-grained permission was sufficient. (at time of writing - Apr 2024)
 
+!!! warning "Deprecation Notice: Implicit Publishing"
+    electron-builder currently auto-detects when to publish based on CI environment conditions:
+
+    - Running via `npm run release` → publishes always
+    - Git tag detected in CI → publishes on tag
+    - CI environment detected → publishes to draft releases
+
+    **This implicit publishing behavior is deprecated and will be disabled in electron-builder v27.**
+
+    To prepare for this change, please explicitly specify your publish intent using the `--publish` CLI flag (e.g., `--publish always`, `--publish onTag`) or set the `publish` configuration in your `package.json` or `electron-builder.yml`.
+
 !!! info "Snap store"
     `snap` target by default publishes to snap store (the app store for Linux). To force publishing to another providers, explicitly specify publish configuration for `snap`.