Remove legacy question storage (#7)

Deletes obsolete question/answer/vote persistence and the compatibility answer endpoint. Existing databases drop the legacy tables through migration 009. Plumber replies now notify the root homeowner even when nested beneath another plumber reply. Post and reply forms prevent duplicate submissions and show progress while posting.

Reviewed-on: #7
Co-authored-by: codegirl-007 <s.raide@gmail.com>

internal/store/sqlc/models.go

@@ -9,14 +9,6 @@ import (
 	"time"
 )
 
-type Answer struct {
-	QuestionID string
-	AuthorID   string
-	Body       string
-	CreatedAt  string
-	UpdatedAt  string
-}
-
 type Post struct {
 	ID        string
 	ParentID  sql.NullString
@@ -36,17 +28,6 @@ type PostVote struct {
 	Value  int32
 }
 
-type Question struct {
-	ID        string
-	AuthorID  string
-	Title     string
-	Body      string
-	City      string
-	HuntDate  string
-	Hidden    int32
-	CreatedAt string
-}
-
 type Session struct {
 	Token  string
 	Data   []byte
@@ -64,9 +45,3 @@ type User struct {
 	State        string
 	CreatedAt    string
 }
-
-type Vote struct {
-	UserID     string
-	QuestionID string
-	Value      int32
-}