rename app data API

Align docs, examples, and tests with AppData and NoData

Update handler, scene, runner, and plugin generics to the new naming

Ignore .codex and record the cleanup in the changelog

plugins.go

@@ -85,13 +85,13 @@ func (c CommandArg) SetRequired() CommandArg {
 }
 
 // CommandExecutor is the function type that executes a command.
-// It receives the message context and a database context (generic).
+// It receives the message context and injected application data.
 // Returning a non-nil error routes it through the bot's error handler.
-type CommandExecutor[T DbContext] func(ctx *MsgContext, dbContext T) error
+type CommandExecutor[T AppData] func(ctx *MsgContext, dbContext T) error
 
 // Command represents a bot command with arguments, description, and executor.
 // Can be registered in a Plugin and optionally skipped from auto-generation.
-type Command[T DbContext] struct {
+type Command[T AppData] struct {
 	command     string                       // The command trigger (e.g., "/start")
 	description string                       // Human-readable description for help
 	exec        CommandExecutor[T]           // Function to execute when command is triggered
@@ -162,7 +162,7 @@ func (c *Command[T]) validateArgs(args []string) error {
 // A Plugin is intended to be fully configured before it is passed to Bot.AddPlugins.
 // After registration, treat the plugin as committed and do not mutate it further.
 // Post-registration changes through the original *Plugin are not a supported API.
-type Plugin[T DbContext] struct {
+type Plugin[T AppData] struct {
 	name        string                       // Name of the plugin (e.g., "admin", "user")
 	commands    map[string]*Command[T]       // Registered commands (triggered by message)
 	payloads    map[string]*Command[T]       // Registered payloads (triggered by callback data)
@@ -177,7 +177,7 @@ type Plugin[T DbContext] struct {
 }
 
 // NewPlugin creates a new Plugin with the given name.
-func NewPlugin[T DbContext](name string) *Plugin[T] {
+func NewPlugin[T AppData](name string) *Plugin[T] {
 	return &Plugin[T]{
 		name:        name,
 		commands:    make(map[string]*Command[T]),
@@ -380,11 +380,11 @@ func (p *Plugin[T]) executeMiddlewares(ctx *MsgContext, db T) bool {
 // MiddlewareExecutor is the function type for middleware logic.
 // Returns true to continue execution, false to block it.
 // If async, return value is ignored.
-type MiddlewareExecutor[T DbContext] func(ctx *MsgContext, db T) bool
+type MiddlewareExecutor[T AppData] func(ctx *MsgContext, db T) bool
 
 // Middleware represents a reusable execution interceptor.
 // Can be synchronous (blocking) or asynchronous (non-blocking).
-type Middleware[T DbContext] struct {
+type Middleware[T AppData] struct {
 	name     string                // Human-readable name for logging/debugging
 	executor MiddlewareExecutor[T] // Function to execute
 	order    int                   // Optional sort order (not used yet)
@@ -392,7 +392,7 @@ type Middleware[T DbContext] struct {
 }
 
 // NewMiddleware creates a new synchronous middleware.
-func NewMiddleware[T DbContext](name string, executor MiddlewareExecutor[T]) Middleware[T] {
+func NewMiddleware[T AppData](name string, executor MiddlewareExecutor[T]) Middleware[T] {
 	return Middleware[T]{name, executor, 0, false}
 }