fix: necessary depencency for Jazzy

[bsutherland333]

An installation path has changed for Jazzy, including it with ament_target_dependencies is necessary to compile: ament/ament_index#84

[Copilot]

Pull Request Overview

This PR fixes a compilation issue with Jazzy by adding the necessary ament_index_cpp dependency to CMakeLists.txt files. This addresses a change in the installation path for Jazzy that requires explicit inclusion of ament_index_cpp as documented in the linked GitHub issue.

• Added ament_index_cpp dependency to two executables that require it for compilation
• Reformatted one dependency list for better readability

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
rosplane_gcs/CMakeLists.txt	Added ament_index_cpp dependency and reformatted the dependency list for rviz_waypoint_publisher
rosplane/CMakeLists.txt	Added ament_index_cpp dependency to the estimator executable

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