binder: apply binder-OCI hardening deltas

[diegocortes3211-design]

This commit applies a series of hardening deltas to the binder-OCI process.

The following changes are included:

• Δ1: Deterministic tarball creation
• Δ2: Binder OCI verification
• Δ3: Workflow fixes
• Δ4: Makefile and verification script updates
• Δ5: Optional receipts index

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