Consolidate Duplicate Filtering Logic

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.