[performance] filter model and database table improvements (#4277)

- removes unnecessary fields / columns (created_at, updated_at)
- replaces filter.context_* columns with singular filter.contexts bit field which should save both struct memory and database space
- replaces filter.action string with integer enum type which should save both struct memory and database space
- adds links from filter to filter_* tables with Filter{}.KeywordIDs and Filter{}.StatusIDs fields (this also means we now have those ID slices cached, which reduces some lookups)
- removes account_id fields from filter_* tables, since there's a more direct connection between filter and filter_* tables, and filter.account_id already exists
- refactors a bunch of the filter processor logic to save on code repetition, factor in the above changes, fix a few bugs with missed error returns and bring it more in-line with some of our newer code

Reviewed-on: https://codeberg.org/superseriousbusiness/gotosocial/pulls/4277
Co-authored-by: kim <grufwub@gmail.com>
Co-committed-by: kim <grufwub@gmail.com>

internal/processing/common/status.go

@@ -213,7 +213,7 @@ func (p *Processor) GetAPIStatus(
 	apiStatus, err := p.converter.StatusToAPIStatus(ctx,
 		target,
 		requester,
-		statusfilter.FilterContextNone,
+		gtsmodel.FilterContextNone,
 		nil,
 	)
 	if err != nil {
@@ -234,7 +234,7 @@ func (p *Processor) GetVisibleAPIStatuses(
 	ctx context.Context,
 	requester *gtsmodel.Account,
 	statuses []*gtsmodel.Status,
-	filterContext statusfilter.FilterContext,
+	filterCtx gtsmodel.FilterContext,
 	filters []*gtsmodel.Filter,
 ) []apimodel.Status {
 
@@ -277,7 +277,7 @@ func (p *Processor) GetVisibleAPIStatuses(
 		apiStatus, err := p.converter.StatusToAPIStatus(ctx,
 			status,
 			requester,
-			filterContext,
+			filterCtx,
 			filters,
 		)
 		if err != nil && !errors.Is(err, statusfilter.ErrHideStatus) {