fix(database): force UTF-8 for embedded Postgres on non-UTF-8 OS locales

[Rooseveltfj]

What is this contribution about?

On a Windows host with a non-UTF-8 OS locale (e.g. Portuguese_Brazil.1252),
the embedded Postgres ends up on WIN1252 at two layers: initdb creates the
cluster using the OS locale, and the pg client connection defaults
client_encoding to WIN1252. Any non-Latin1 character in seeded data (e.g. the
→ arrows in the default connection metadata) then fails to encode and the
INSERT throws 22P05 (untranslatable character).

The impact is not just a log error: it aborts the organization-creation hook
during local admin seeding, leaving the database half-seeded — the user can
then never log in ("Local admin user not found").

This forces UTF-8 at both layers:

• initdb runs with --encoding=UTF8 --locale=C, so the cluster is created in
  UTF-8 regardless of the OS locale.
• The pg pools pass options: "-c client_encoding=UTF8", so the session
  encoding is UTF-8 on every connection.

No-op on systems already on a UTF-8 locale (macOS/Linux).

How to Test

1. On a Windows host with a non-UTF-8 locale, start from a clean .deco
2. Run bun run dev and open http://localhost:3000
3. Expected: local admin is seeded, auto-login succeeds, no 22P05 in the logs

Migration Notes

The initdb flags apply to newly created clusters; the client_encoding
option applies to every new connection. Existing UTF-8 setups are unchanged.

Review Checklist

• PR title is clear and descriptive
• Changes are tested and working
• No breaking changes (no-op on UTF-8 locales)

---

Summary by cubic

Forces UTF-8 for embedded Postgres and client sessions to avoid encoding errors on Windows non‑UTF‑8 locales. Prevents seeding failures (22P05) and allows local admin auto‑login; no‑op on UTF‑8 systems.

• Bug Fixes

  • Run initdb with --encoding=UTF8 --locale=C --locale-provider=libc for embedded clusters.
  • Set pool options: "-c client_encoding=UTF8" for all Postgres connections.

• Migration

  • initdb flags affect new clusters only; existing UTF‑8 setups are unchanged.

^{Written for commit 0394736. Summary will update on new commits.}

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