fix(gbrain-local-status): classifier falsely reports broken-db inside repos with their own DATABASE_URL

The freshClassify probe ran `gbrain sources list --json` with the inherited
process env. When the probe ran from inside a repo with its own .env (an app
DATABASE_URL on a different port), Bun autoloaded the project's .env, gbrain
connected to the wrong database, and the classifier reported broken-db on
otherwise-healthy brains.

Fix: route the probe env through `buildGbrainEnv` from lib/gbrain-exec, the
same helper the sync orchestrator uses. DATABASE_URL is seeded from
~/.gbrain/config.json so the result is cwd-independent. The 60s cache can no
longer propagate a poisoned negative to clean directories.

Contributed by @jetsetterfl via #1583.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

lib/gbrain-local-status.ts

@@ -35,6 +35,7 @@ import {
 } from "fs";
 import { homedir } from "os";
 import { dirname, join } from "path";
+import { buildGbrainEnv } from "./gbrain-exec";
 
 export type LocalEngineStatus =
   | "ok"
@@ -226,12 +227,20 @@ function freshClassify(env?: NodeJS.ProcessEnv): LocalEngineStatus {
   if (!existsSync(gbrainConfigPath())) return "missing-config";
 
   // 3. Probe gbrain sources list.
+  //
+  // Seed DATABASE_URL from ~/.gbrain/config.json (via buildGbrainEnv, the
+  // same helper the sync orchestrator uses in lib/gbrain-exec.ts). Without
+  // this, Bun autoloads a project's .env when the probe runs inside a repo
+  // that defines its own DATABASE_URL (e.g. an app DB on a different port),
+  // gbrain connects to the wrong DB, and the classifier falsely reports
+  // broken-db. This also makes the result cwd-independent, so the 60s cache
+  // can no longer propagate a poisoned negative to clean directories.
   try {
     execFileSync("gbrain", ["sources", "list", "--json"], {
       encoding: "utf-8",
       timeout: PROBE_TIMEOUT_MS,
       stdio: ["ignore", "pipe", "pipe"],
-      env: env ?? process.env,
+      env: buildGbrainEnv({ baseEnv: env ?? process.env }),
     });
     return "ok";
   } catch (err) {