fix(setup): identify Sim compose projects by content, not filename

Cursor (High): composeInstalls treated any project whose config basename was docker-compose.prod.yml or docker-compose.local.yml as a Sim install. Those names are common, and sim reset runs 'compose down -v' — so a stranger's stack could have had its volumes destroyed.

I introduced that reach. The previous ROOT-scoped '-f' probe was implicitly safe because it could only ever see the project in this checkout; switching to a global 'compose ls' to find stacks started elsewhere means projects must be identified by content instead. Read the config file Docker recorded and require a Sim marker (the published app image, or the app Dockerfile this repo builds), so both the prod and local variants match while an unrelated file with the same name does not. An unreadable or since-deleted file is left unmanaged rather than assumed ours.

Verified against a decoy nginx compose file using our exact filename: ignored, while both real Sim compose files still match.

Author: TheodoreSpeaks

scripts/setup/lifecycle.ts

@@ -1,4 +1,5 @@
 import { spawnSync } from 'node:child_process'
+import { readFileSync } from 'node:fs'
 import path from 'node:path'
 import { DB_CONTAINER, type Detection, REDIS_CONTAINER, runDetection } from './detect.ts'
 import { archiveEnvFile, ROOT } from './env-files.ts'
@@ -90,6 +91,33 @@ interface ComposeProject {
   ConfigFiles: string
 }
 
+/**
+ * Markers that a compose file is actually Sim's: the published app image
+ * (docker-compose.prod.yml) or the app Dockerfile this repo builds
+ * (docker-compose.local.yml).
+ */
+const SIM_COMPOSE_MARKERS = ['ghcr.io/simstudioai/simstudio', 'docker/app.Dockerfile'] as const
+
+/**
+ * `docker-compose.prod.yml` is a common filename, so the name alone cannot say a
+ * project is ours — and `sim reset` runs `compose down -v`, which would destroy
+ * an unrelated stack's volumes. Read the file Docker recorded for the project and
+ * require a Sim marker inside it. The old ROOT-scoped `-f` probe was implicitly
+ * safe because it could only ever see the local project; discovering projects
+ * globally means identifying them by content instead.
+ */
+function isSimComposeFile(file: string): boolean {
+  if (!(COMPOSE_FILES as readonly string[]).includes(path.basename(file))) return false
+  try {
+    const contents = readFileSync(file, 'utf8')
+    return SIM_COMPOSE_MARKERS.some((marker) => contents.includes(marker))
+  } catch {
+    // Unreadable or deleted since the stack started — better to not manage it
+    // than to guess from the filename.
+    return false
+  }
+}
+
 /**
  * Ask Docker which compose projects exist rather than guessing from the working
  * directory. Compose derives a project name from the directory it was started
@@ -98,8 +126,7 @@ interface ComposeProject {
  * — and it reports the same stack once per candidate file, since both files map
  * to the same directory-derived project. `compose ls` records the real project
  * and the exact config file, so one running stack yields exactly one install
- * wherever it was started from. Projects whose compose file isn't one of ours
- * (a devcontainer, an unrelated app) are filtered out by filename.
+ * wherever it was started from.
  */
 function composeInstalls(): ComposeInstall[] {
   const raw = dockerText(['compose', 'ls', '-a', '--format', 'json'])
@@ -116,7 +143,7 @@ function composeInstalls(): ComposeInstall[] {
     const file = (project.ConfigFiles ?? '')
       .split(',')
       .map((entry) => entry.trim())
-      .find((entry) => (COMPOSE_FILES as readonly string[]).includes(path.basename(entry)))
+      .find(isSimComposeFile)
     if (!file) continue
     installs.push({
       kind: 'compose',