Feature/Incremental slot_duration

[iceseer]

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Description

What Was Done
The main change involves transitioning from time-based slot calculation logic to incremental slot calculation logic in the AURA consensus for parachains. Instead of calculating slots based on time (S_i = T/D), an incremental logic (S_i = S_{i-1} + 1) is now used.

Key Changes:

1. New slot_tracker.rs Module
   Created new IncrementalSlotTracker module for client-side slot tracking
   Implements S_i = S_{i-1} + 1 logic on the client side
   Uses atomic operations for thread-safety
   Supports initialization from storage and fallback to timestamp-based calculation
2. Changes in collator.rs
   claim_slot function now accepts IncrementalSlotTracker instead of slot_duration
   Removed time-based slot calculation logic, replaced with slot_tracker.current_slot()
   Added comments about client-side slot calculation
3. Changes in basic.rs
   Added global slot tracker initialization
   Initialization happens once with storage reading
   Fallback to zero slot on initialization error
   Passing tracker to claim_slot
4. Changes in lookahead.rs
   Similar slot tracker initialization
   Modified can_build_upon logic to use tracker
   Removed time-based slot calculation logic
5. Changes in equivocation_import_queue.rs
   slot_now function now first tries to use global tracker
   Fallback to timestamp-based calculation if tracker not initialized
6. Changes in consensus_hook.rs
   Removed parachain slot alignment check with relay chain slot
   Removed time-based slot calculation logic
   Kept only velocity management and relay chain synchronization logic
7. Changes in aura-ext/src/lib.rs
   Removed LastParachainSlot storage - tracking moved to client side
   Added comments about moving logic to client
8. Changes in slot_timer.rs
   Added comment that timing remains timestamp-based, but slot index comes from incremental API
9. Dependencies
   Added frame-support dependency in Cargo.toml

Integration

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