Add Kiro terminal integration

[xtetsuji]

No description provided.

[Copilot]

Pull Request Overview

This PR adds conditional shell integration support for the Kiro terminal emulator, following the established pattern used for other development tools in the repository.

• Adds Kiro terminal integration that sources shell-specific integration scripts when running in the Kiro terminal
• Uses the existing exists, shell_name, and source_if_readable utility functions
• Follows the same structure as direnv integration (lines 127-134)

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[Copilot]

The conditional check for shell_name on line 147 is unnecessary. Unlike the zoxide and mise integrations (lines 196-215) that verify shell_name exists as a function with exists shell_name, the direnv integration (lines 128-134) directly uses shell_name without this check. Since shell_name is defined in path_functions which is sourced before common_env, and returns an empty string for unsupported shells, the inner check is redundant. If the empty string is a concern, it would be caught by the subsequent validation on line 149. Consider simplifying to match the direnv pattern or add the exists shell_name check in the outer condition to match zoxide/mise.

Suggested change

	if [ -n "$shell" ]; then
	kiro_integration_path="$(kiro --locate-shell-integration-path "$shell" 2>/dev/null)"
	if [ -n "$kiro_integration_path" ]; then
	source_if_readable "$kiro_integration_path"
	fi
	unset kiro_integration_path
	fi
	kiro_integration_path="$(kiro --locate-shell-integration-path "$shell" 2>/dev/null)"
	if [ -n "$kiro_integration_path" ]; then
	source_if_readable "$kiro_integration_path"
	fi
	unset kiro_integration_path

[xtetsuji]

duplicated? #52