Refactor prompt options and forms to use PromptConfiguration for improved extensibility

[shibayan]

This pull request refactors the prompt form classes to improve code reuse and configuration handling, especially for selection-based prompts. The changes introduce a new abstract base class for selection forms, streamline paginator and key handler management, and ensure that prompt configuration is consistently passed throughout the forms. Additionally, resource disposal is improved to prevent leaks.

Refactoring and abstraction of selection forms:

• Introduced a new abstract base class SelectFormBase<TItem, TResult> to encapsulate common logic for selection-based forms (SelectForm and MultiSelectForm), including paginator initialization, key handler mapping, text input handling, and pagination rendering. (Sharprompt/Forms/SelectFormBase.cs)
• Updated SelectForm<T> and MultiSelectForm<T> to inherit from SelectFormBase, removing duplicated paginator and key handler logic, and delegating shared functionality to the base class. (Sharprompt/Forms/SelectForm.cs, Sharprompt/Forms/MultiSelectForm.cs) [1] [2]

Prompt configuration propagation:

• Modified constructors of all form classes to accept a PromptConfiguration parameter and consistently use it for rendering and symbol selection. This ensures that all forms are properly configured and customizable. (Sharprompt/Forms/FormBase.cs, Sharprompt/Forms/ConfirmForm.cs, Sharprompt/Forms/InputForm.cs, Sharprompt/Forms/ListForm.cs, Sharprompt/Forms/PasswordForm.cs, Sharprompt/Forms/SelectForm.cs, Sharprompt/Forms/MultiSelectForm.cs) [1] [2] [3] [4] [5] [6] [7]

Resource management improvements:

• Changed disposal logic in FormBase and related classes to ensure that the console driver is disposed rather than just the renderer, addressing potential resource leaks. (Sharprompt/Forms/FormBase.cs, Sharprompt/Forms/FormRenderer.cs) [1] [2]

Options and validation updates:

• Updated ConfirmOptions and InputOptions<T> to inherit from PromptOptions and removed redundant EnsureOptions methods, simplifying options validation and inheritance. (Sharprompt/ConfirmOptions.cs, Sharprompt/InputOptions.cs) [1] [2]

Rendering and buffer improvements:

• Refactored OffscreenBuffer to accept PromptConfiguration for consistent rendering and symbol usage across all prompts. (Sharprompt/Internal/OffscreenBuffer.cs)

[Copilot]

Pull request overview

This PR refactors Sharprompt’s form and options infrastructure to centralize configuration (colors/symbols/driver factory) via PromptConfiguration, reduce duplication across selection-based forms, and tighten resource ownership around the console driver lifecycle.

Changes:

• Introduces PromptConfiguration and updates forms/rendering/buffer code to consistently use it (symbols/colors, cancel behavior, driver factory).
• Adds a shared PromptOptions base type for common option fields/validation and updates existing option types to inherit from it.
• Refactors SelectForm and MultiSelectForm to share pagination/filter/key handling via a new SelectFormBase<TItem, TResult>.

Reviewed changes

Copilot reviewed 22 out of 22 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
Sharprompt/SelectOptions.cs	Inherits from PromptOptions; validation now calls base.EnsureOptions().
Sharprompt/PromptOptions.cs	Adds shared Message + EnsureOptions() for option validation.
Sharprompt/PromptConfiguration.cs	Adds configuration object for driver factory, symbols, and color schema.
Sharprompt/Prompt.Configuration.cs	Routes existing Prompt.* configuration APIs through PromptConfiguration.
Sharprompt/Prompt.Basic.cs	Passes shared configuration into forms to ensure consistent rendering/behavior.
Sharprompt/PasswordOptions.cs	Inherits from PromptOptions; validation calls base.EnsureOptions().
Sharprompt/MultiSelectOptions.cs	Inherits from PromptOptions; validation calls base.EnsureOptions().
Sharprompt/ListOptions.cs	Inherits from PromptOptions; validation calls base.EnsureOptions().
Sharprompt/Internal/OffscreenBufferExtensions.cs	Uses OffscreenBuffer.Configuration for symbols/colors instead of static Prompt.*.
Sharprompt/Internal/OffscreenBuffer.cs	Takes PromptConfiguration; no longer owns/implements disposal for the console driver.
Sharprompt/InputOptions.cs	Inherits from PromptOptions and removes redundant EnsureOptions() implementation.
Sharprompt/Forms/TextFormBase.cs	Requires PromptConfiguration and forwards it to FormBase.
Sharprompt/Forms/SelectFormBase.cs	New shared base class for selection-form paging/filtering and key handling.
Sharprompt/Forms/SelectForm.cs	Refactored to inherit from SelectFormBase and use Configuration for symbols.
Sharprompt/Forms/PasswordForm.cs	Constructor updated to accept PromptConfiguration.
Sharprompt/Forms/MultiSelectForm.cs	Refactored to inherit from SelectFormBase and use Configuration for symbols.
Sharprompt/Forms/ListForm.cs	Constructor updated to accept PromptConfiguration.
Sharprompt/Forms/InputForm.cs	Constructor updated to accept PromptConfiguration.
Sharprompt/Forms/FormRenderer.cs	Now constructed with configuration; no longer disposable (lifetime moved to driver).
Sharprompt/Forms/FormBase.cs	Accepts PromptConfiguration, constructs renderer with it, and disposes the console driver.
Sharprompt/Forms/ConfirmForm.cs	Constructor updated to accept PromptConfiguration.
Sharprompt/ConfirmOptions.cs	Inherits from PromptOptions and removes redundant EnsureOptions().

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[Copilot]

FormBase stores and uses the passed PromptConfiguration but doesn't validate it for null. If a null configuration is ever passed, this will result in a NullReferenceException when accessing configuration.ConsoleDriverFactory() or later when reading _configuration.ThrowExceptionOnCancel. Consider adding ArgumentNullException.ThrowIfNull(configuration); at the start of the constructor to fail fast with a clear exception.

Suggested change

	{
	{
	ArgumentNullException.ThrowIfNull(configuration);