V118 DIRECT LOCAL ACCOUNT CREATE / LOGIN

Purpose of this build:
- Make CREATE ACCOUNT and LOG IN work first, independently from character-folder routing.
- No account server.
- No URL protocol.
- No Python background helper.
- No request/reply mailbox.
- No automatic character backup, restore, copy, sync, or respawn.

Flow inside BG2:
1. Enter Account name.
2. Enter Password.
3. Enter Confirm Password.
4. CREATE ACCOUNT lights only when the name is new and the two 8-128 character passwords match.
5. CREATE ACCOUNT stores a one-way SHA-256 verifier as numeric BG2 INI values in Baldur.lua.
6. The password and confirmation remain in the fields after creation.
7. CREATE ACCOUNT becomes unavailable for that account and LOG IN becomes available.
8. LOG IN checks the entered password locally.
9. Correct password logs into that account and enables CONTINUE.
10. Wrong password does not authenticate.

Account names are case-insensitive and allow 1-32 letters, numbers, underscore, or hyphen.
The plaintext password is not stored.

Character folders are intentionally NOT connected in V118. That is the next isolated step after create/login is confirmed working in BG2/Moonlight.
