Fix embedded Postgres initdb failure in Docker slim containers

The embedded-postgres library hardcodes --lc-messages=en_US.UTF-8 and
strips the parent process environment when spawning initdb/postgres.
In slim Docker images (e.g. node:20-bookworm-slim), the en_US.UTF-8
locale isn't installed, causing initdb to exit with code 1.

Two fixes applied:
1. Add --lc-messages=C to all initdbFlags arrays (overrides the
   library's hardcoded locale since our flags come after in the spread)
2. pnpm patch on embedded-postgres to preserve process.env in spawn
   calls, preventing loss of PATH, LD_LIBRARY_PATH, and other vars

Co-Authored-By: Paperclip <noreply@paperclip.ing>

cli/src/__tests__/company-import-export-e2e.test.ts

@@ -63,7 +63,7 @@ async function startTempDatabase() {
     password: "paperclip",
     port,
     persistent: true,
-    initdbFlags: ["--encoding=UTF8", "--locale=C"],
+    initdbFlags: ["--encoding=UTF8", "--locale=C", "--lc-messages=C"],
     onLog: () => {},
     onError: () => {},
   });

cli/src/commands/worktree.ts

@@ -756,7 +756,7 @@ async function ensureEmbeddedPostgres(dataDir: string, preferredPort: number): P
     password: "paperclip",
     port,
     persistent: true,
-    initdbFlags: ["--encoding=UTF8", "--locale=C"],
+    initdbFlags: ["--encoding=UTF8", "--locale=C", "--lc-messages=C"],
     onLog: () => {},
     onError: () => {},
   });