refactor!: retire wails.json, config.yml is the version source

- version.go (generated, never hand-edited) carries the compiled-in
  version; app.go drops the wails.json embed plus the gjson dependency
- make release bumps config.yml and regenerates version.go in one
  commit; the re-run-safe guards from the 1.99.1 cycle carry over
- release guard reads config.yml; CI CLI pin and cache key move to
  beta.22 to match the lockstep above
- release wrapper and config NOTE comments updated; deletion proof:
  wails3 build green plus a dev boot reaching the connected state
  with the file absent (the one cold-boot failure reproduced as a
  Vite 8 cold-start vs app retry race, cleared by rerunning warm)

app.go

@@ -1,16 +1,11 @@
 package main
 
 import (
-	_ "embed"
 	"strings"
 
-	"github.com/tidwall/gjson"
 	"github.com/wailsapp/wails/v3/pkg/application"
 )
 
-//go:embed wails.json
-var wailsJSON string
-
 // App struct
 type App struct {
 	app *application.App
@@ -21,9 +16,10 @@ func NewApp(app *application.App) *App {
 	return &App{app: app}
 }
 
-// appVersion reads the product version from wails.json.
+// appVersion is the release version, stamped into version.go by
+// `make release` from build/config.yml.
 func appVersion() string {
-	return gjson.Get(wailsJSON, "info.productVersion").String()
+	return appVersionString
 }
 
 // appTitle is the window title: "AniTrack <version>".