BizCore v4.5 - Batch / Lot Traceability & Expiry Management

USER-FRIENDLY DESIGN
- Existing normal inventory workflow remains unchanged.
- Production batches are captured automatically only when a batch number is entered.
- Batch / Lot Stock gives one simple stock view.
- Expiry Dashboard focuses only on items requiring attention.
- Batch Traceability searches one batch number and shows its movement history.

INSTALL
1. Take database + file backup.
2. Upload ZIP to existing BizCore root and Extract > Overwrite.
3. Open https://ceylongemx.online/update-4.5.php
4. Click Install v4.5 Update.
5. Confirm both new tables show OK.
6. Ctrl+F5.

IMPORTANT
- v4.5 starts batch balance tracking for NEW production postings after installation.
- Existing historical stock is not guessed or silently converted into batches.
- Core stock_balances remains the authoritative overall inventory balance.
- Sales/POS FEFO allocation is intentionally NOT forced in this update because the supplied package does not contain the current POS/sales source files; this avoids breaking live sales.
