docs+cli: deprecate prompt targets and remove generate_prompt_targets command (#944)

Prompt targets are no longer actively maintained.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.

docs/source/concepts/prompt_target.rst

@@ -2,6 +2,15 @@
 
 Prompt Target
 =============
+
+.. deprecated:: v0.4.22
+   **Prompt Targets are deprecated and no longer actively maintained.** This concept is
+   retained for existing users on older Plano configurations, but new applications should
+   not adopt it. For deterministic, task-specific workloads, use :ref:`Agents <agents>`
+   together with :ref:`Function Calling <function_calling>` instead. The
+   ``prompt_targets`` configuration block and related CLI commands will continue to
+   function for now, but may be removed in a future release.
+
 A Prompt Target is a deterministic, task-specific backend function or API endpoint that your application calls via Plano.
 Unlike agents (which handle wide-ranging, open-ended tasks), prompt targets are designed for focused, specific workloads where Plano can add value through input clarification and validation.
 

docs/source/get_started/overview.rst

@@ -57,10 +57,10 @@ Deep dive into essential ideas and mechanisms behind Plano:
 
         Explore Plano's LLM integration options
 
-    .. grid-item-card:: :octicon:`workflow` Prompt Target
+    .. grid-item-card:: :octicon:`workflow` Prompt Target (Deprecated)
         :link: ../concepts/prompt_target.html
 
-        Understand how Plano handles prompts
+        Deprecated — kept for existing users. New apps should use Agents.
 
 
 Guides

docs/source/get_started/quickstart.rst

@@ -247,6 +247,11 @@ You can then ask a follow-up like "Also book me a hotel near JFK" and Plano-Orch
 Deterministic API calls with prompt targets
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
+.. deprecated:: v0.4.22
+   :ref:`Prompt Targets <prompt_target>` are deprecated and no longer actively
+   maintained. The walkthrough below is preserved for users on existing configs;
+   new applications should use :ref:`Agents <agents>` instead.
+
 Next, we'll show Plano's deterministic API calling using a single prompt target. We'll build a currency exchange backend powered by `https://api.frankfurter.dev/`, assuming USD as the base currency.
 
 Step 1. Create plano config file

docs/source/guides/function_calling.rst

@@ -6,6 +6,12 @@ Function Calling
 **Function Calling** is a powerful feature in Plano that allows your application to dynamically execute backend functions or services based on user prompts.
 This enables seamless integration between natural language interactions and backend operations, turning user inputs into actionable results.
 
+.. deprecated:: v0.4.22
+   The prompt-target based workflow shown below (see :ref:`Step 2 <function_calling>`)
+   is deprecated. :ref:`Prompt Targets <prompt_target>` are no longer actively
+   maintained and may be removed in a future release. For new function-calling
+   workloads, prefer :ref:`Agents <agents>` with tool definitions.
+
 
 What is Function Calling?
 -------------------------

docs/source/resources/cli_reference.rst

@@ -16,7 +16,6 @@ Quick Navigation
 - :ref:`cli_reference_logs`
 - :ref:`cli_reference_init`
 - :ref:`cli_reference_trace`
-- :ref:`cli_reference_prompt_targets`
 - :ref:`cli_reference_cli_agent`
 
 
@@ -260,24 +259,6 @@ Inspect request traces from the local OTLP listener.
 - ``--list`` cannot be combined with a specific trace-id target.
 
 
-.. _cli_reference_prompt_targets:
-
-planoai prompt_targets
-----------------------
-
-Generate prompt-target metadata from Python methods.
-
-**Synopsis**
-
-.. code-block:: console
-
-   $ planoai prompt_targets --file <python-file>
-
-**Options**
-
-- ``--file, --f <python-file>``: required path to a ``.py`` source file.
-
-
 .. _cli_reference_cli_agent:
 
 planoai cli_agent