fix(sandboxes): let a same-spec save retry a failed build

Cursor Bugbot. `scheduleSandboxBuild` sat inside the changed-hash branch, so a save
that did not alter the package list never reached the registry. The comment above
it described the opposite — that an unchanged spec finds a ready row and enqueues
nothing — which is what `ensureSandboxImage` does, but only if it is called.

That made the docs wrong too. They tell a reader to save the sandbox again to retry
a failed build immediately, and this branch is exactly why that did nothing: the
only way to retry was to edit the package list into a different hash, which is not
what someone recovering from a transient registry failure wants to do.

The call is now unconditional and the registry decides what a save costs, which is
what its conflict guard is for: a ready or in-flight row is left alone, a failed one
is re-claimed at once. Releasing the previous image stays behind the hash check,
since only a changed hash orphans one. Cache invalidation is unchanged —
`scheduleSandboxBuild` already does it, which is why the else branch existed.

Co-Authored-By: Claude <noreply@anthropic.com>

Author: icecrasher321

apps/sim/app/api/workspaces/[id]/sandboxes/[sandboxId]/route.ts

@@ -86,16 +86,19 @@ export const PATCH = withRouteHandler(async (request: NextRequest, context: Sand
     throw error
   }
 
-  // An unchanged spec re-points at the same content address, so `ensureSandboxImage`
-  // finds a `ready` row and enqueues nothing. Editing the name alone costs no build.
+  // Unconditional, because the registry decides what a save costs: a `ready` or
+  // in-flight row is left alone, so renaming or re-saving an unchanged spec
+  // enqueues nothing, while a failed one gets the immediate retry a person saving
+  // is asking for. Gating this on a changed hash meant a same-spec save silently
+  // did nothing, and the only way to retry a failed build was to edit the package
+  // list into a different hash.
+  await scheduleSandboxBuild(spec)
+
   if (spec.specHash !== existing.specHash) {
-    await scheduleSandboxBuild(spec)
     // The previous content address is unreferenced by this sandbox now. Release
     // no-ops when another sandbox still declares the same package list.
     runDetached('release-sandbox-image', () => releaseSandboxImage(existing.specHash))
     logger.info('Sandbox spec changed, scheduled a build', { workspaceId, sandboxId })
-  } else {
-    invalidateSandboxResolution()
   }
 
   const sandbox = await readWorkspaceSandbox(workspaceId, sandboxId)