Prompt targets are no longer actively maintained. Mark them as deprecated in
the docs and remove the `planoai generate_prompt_targets` CLI command that
existed only to scaffold them.
Docs
- Add `.. deprecated::` banner to the Prompt Target concept page and to the
function-calling guide / quickstart sections that walk users through
configuring prompt targets.
- Relabel the Prompt Target card on the overview page as deprecated.
- Drop the Prompt Targets bullet from the README's Getting Started list.
CLI
- Remove the `generate_prompt_targets` Click command, its registration, and
the `Utilities` rich-click command group.
- Delete `cli/planoai/targets.py` (the command's only consumer).
- Drop the `planoai prompt_targets` section from the CLI reference page.
Skills
- Delete the `cli-generate` rule, drop it from `plano-cli-operations`
(description, when-to-use, rules list, execution checklist), and update
the skills README. Hand-edit AGENTS.md to remove section 6.2 and renumber
6.3/6.4 so the commit stays scoped (regenerating pulled in unrelated
drift between rules/ and AGENTS.md).
The runtime gateway, schema, and existing demo configs still accept
`prompt_targets` blocks; this is deprecation, not removal of behavior.
