Consolidate Duplicate Filtering Logic

[arya2004]

Both filter.go and model/packet.go have similar or identical ciMatch and filtering logic (Apply, ApplyFilters). This is redundant and makes maintenance harder.

Task:

• Move all filtering logic to the model package (model/packet.go).
• Remove redundant code from filter.go and delete the file.
• Update any imports/usages of the filtering logic in other files (e.g., client.go).

Tip:
Replace usages like filter.ApplyFilters(...) with model.ApplyFilters(...) and adjust arguments if needed.

Why:
This makes the codebase easier to maintain and reduces bugs due to logic duplication.

[princyballabh]

Hey! Can you please assign this issue to me? I would be glad to work on this.