[performance] cache more database calls, reduce required database calls overall (#3290)

* improvements to caching for lists and relationship to accounts / follows

* fix nil panic in AddToList()

* ensure list related caches are correctly invalidated

* ensure returned ID lists are ordered correctly

* bump go-structr to v0.8.9 (returns early if zero uncached keys to be loaded)

* remove zero checks in uncached key load functions (go-structr now handles this)

* fix issues after rebase on upstream/main

* update the expected return order of CSV exports (since list entries are now down by entry creation date)

* rename some funcs, allow deleting list entries for multiple follow IDs at a time, fix up more tests

* use returning statements on delete to get cache invalidation info

* fixes to recent database delete changes

* fix broken list entries delete sql

* remove unused db function

* update remainder of delete functions to behave in similar way, some other small tweaks

* fix delete user sql, allow returning on err no entries

* uncomment + fix list database tests

* update remaining list tests

* update envparsing test

* add comments to each specific key being invalidated

* add more cache invalidation explanatory comments

* whoops; actually delete poll votes from database in the DeletePollByID() func

* remove added but-commented-out field

* improved comment regarding paging being disabled

* make cache invalidation comments match what's actually happening

* fix up delete query comments to match what is happening

* rename function to read a bit better

* don't use ErrNoEntries on delete when not needed (it's only needed for a RETURNING call)

* update function name in test

* move list exclusivity check to AFTER eligibility check. use log.Panic() instead of panic()

* use the poll_id column in poll_votes for selecting votes in poll ID

* fix function name

3 files changed, 7 insertions, 1 deletions

diff --git a/vendor/codeberg.org/gruf/go-structr/cache.go b/vendor/codeberg.org/gruf/go-structr/cache.go
index 8fcd4fec4..e73db58f8 100644
--- a/vendor/codeberg.org/gruf/go-structr/cache.go
+++ b/vendor/codeberg.org/gruf/go-structr/cache.go
@@ -375,6 +375,11 @@ func (c *Cache[T]) Load(index *Index, keys []Key, load func([]Key) ([]T, error))
 	// the lock.
 	unlock()
 
+	if len(keys) == 0 {
+		// We loaded everything!
+		return values, nil
+	}
+
 	// Load uncached values.
 	uncached, err := load(keys)
 	if err != nil {
diff --git a/vendor/codeberg.org/gruf/go-structr/item.go b/vendor/codeberg.org/gruf/go-structr/item.go
index 97079c378..bf83f1444 100644
--- a/vendor/codeberg.org/gruf/go-structr/item.go
+++ b/vendor/codeberg.org/gruf/go-structr/item.go
@@ -41,7 +41,6 @@ func free_indexed_item(item *indexed_item) {
 }
 
 // drop_index will drop the given index entry from item's indexed.
-// note this also handles freeing the index_entry memory (e.g. to pool)
 func (i *indexed_item) drop_index(entry *index_entry) {
 	for x := 0; x < len(i.indexed); x++ {
 		if i.indexed[x] != entry {
diff --git a/vendor/codeberg.org/gruf/go-structr/runtime.go b/vendor/codeberg.org/gruf/go-structr/runtime.go
index 44fdd74a7..d2bdba380 100644
--- a/vendor/codeberg.org/gruf/go-structr/runtime.go
+++ b/vendor/codeberg.org/gruf/go-structr/runtime.go
@@ -152,8 +152,10 @@ func extract_fields(ptr unsafe.Pointer, fields []struct_field) []unsafe.Pointer
 			fptr = field.zero
 		}
 
+		// Set field ptr.
 		ptrs[i] = fptr
 	}
+
 	return ptrs
 }