Add @extends to application query classes
Summary:
Help improve IDE completion and make phpstan happier at `--level 2` and above
by fairly mechanically applying phpdoc strings to the top of each `*Query`
class to annotate what kinds of objects `execute()` and friends will return.
Closes T16179
Test Plan:
Run phpstan at a few different levels to ensure the reductions are true.
| Level | Before | After | Change
|-------|--------|-------|-------
| 1 | 1817 | 1818 | 1
| 2 | 5497 | 5217 | -280
| 3 | 5825 | 5546 | -279
| 4 | 7051 | 6771 | -280
The increase in level 1 is because the type annotation reveals a latent bug.
There isn't a //decrease// at level 1 because the static analysis that Lv1 does
is insufficiently strong to take these annotations into account except very
superficially. At Lv1, these changes primarily help IDE users get better hover
context and completion suggestions.
Reviewers: O1 Blessed Committers, aklapper, valerio.bozzolan
Reviewed By: O1 Blessed Committers, aklapper, valerio.bozzolan
Subscribers: aklapper, tobiaswiese, valerio.bozzolan, Matthew, Cigaryno
Maniphest Tasks: T16179
Differential Revision: https://we.phorge.it/D26218