V162 - ACCOUNT IDS + AUTOMATIC CHARACTER SAVE - NO MANUAL EXPORT - NO BACKUPS

Behavior:
1. ACCOUNT MIRROR
   - Login connects BG2's literal characters path directly to characters_<accountname>.
   - Account isolation remains unchanged.

2. CHARACTER IMPORT
   - Native Import Character remains available in CHARGEN.
   - Import Saved Game and Pregenerate routes are disabled.
   - Selecting an imported account character remembers its filename for stable-ID ownership.

3. STABLE ACCOUNT CHARACTER IDS
   - Final character-creation ACCEPT allocates the next account id.
   - Drakhysys -> dra_1, dra_2, dra_3, ...
   - Kronas -> kro_1, kro_2, kro_3, ...
   - Other accounts use their first three alphanumeric account letters.
   - Imported legacy names are assigned a stable id; the legacy filename is removed only after the first successful autosave.
   - The visible in-game character name is not changed by the file id.

4. AUTOMATIC CHARACTER SAVE
   - Manual Export Character is removed from the record screen.
   - After character creation is accepted, the first account-character autosave is queued immediately.
   - During gameplay, the same character id is refreshed every five minutes.
   - BG2 first exports to the reserved temporary name __DASV__, then the local router atomically replaces the stable id file.
   - Existing dra_1 / kro_1 is replaced in place; no dra_1(1), dra_1_2, backup history, or restore copy is created.

5. NO AUTOMATIC CHARACTER BACKUPS
   - No CHR/BIO backup copy is created.
   - Once a stable id has been saved, deleting its CHR stops autosave for that character; it is not recreated.
   - Deleted account characters are not restored from a backup.
   - The character-id metadata file stores only the last allocated number per account; it does not contain character data.

Install with SETUP_IN_GAME_ACCOUNTS.bat.
