[command] Add dependency analysis command (#10)

Author: coisa

README.md

@@ -16,6 +16,8 @@ across Fast Forward libraries.
 
 - Aggregates refactoring, PHPDoc, code style, tests, and reporting under a
   single Composer-facing command vocabulary
+- Adds dependency analysis for missing and unused Composer packages through a
+  single report entrypoint
 - Ships shared workflow stubs, `.editorconfig`, Dependabot configuration, and
   other onboarding defaults for consumer repositories
 - Synchronizes packaged agent skills into consumer `.agents/skills`
@@ -47,6 +49,10 @@ You can also run individual commands for specific development tasks:
 # Run PHPUnit tests
 composer dev-tools tests
 
+# Analyze missing and unused Composer dependencies
+composer dependencies
+vendor/bin/dev-tools dependencies
+
 # Check and fix code style using ECS and Composer Normalize
 composer dev-tools code-style
 
@@ -77,6 +83,13 @@ composer dev-tools gitignore
 composer dev-tools:sync
 ```
 
+The `dependencies` command expects both dependency analyzers to be installed in
+the target project:
+
+```bash
+composer require --dev shipmonk/composer-dependency-analyser icanhazstring/composer-unused
+```
+
 The `skills` command keeps `.agents/skills` aligned with the packaged Fast
 Forward skill set. It creates missing links, repairs broken links, and
 preserves existing non-symlink directories. The `dev-tools:sync` command calls
@@ -89,6 +102,7 @@ automation assets.
 |---------|---------|
 | `composer dev-tools` | Runs the full `standards` pipeline. |
 | `composer dev-tools tests` | Runs PHPUnit with local-or-packaged configuration. |
+| `composer dependencies` | Reports missing and unused Composer dependencies. |
 | `composer dev-tools docs` | Builds the HTML documentation site from PSR-4 code and `docs/`. |
 | `composer dev-tools skills` | Creates or repairs packaged skill links in `.agents/skills`. |
 | `composer dev-tools:sync` | Updates scripts, workflow stubs, `.editorconfig`, `.gitignore`, wiki setup, and packaged skills. |

docs/api/commands.rst

@@ -30,6 +30,9 @@ resolution, configuration fallback, PSR-4 lookup, and child-command dispatch.
    * - ``FastForward\DevTools\Command\TestsCommand``
      - ``tests``
      - Runs PHPUnit with optional coverage output.
+   * - ``FastForward\DevTools\Command\DependenciesCommand``
+     - ``dependencies``
+     - Reports missing and unused Composer dependencies.
    * - ``FastForward\DevTools\Command\DocsCommand``
      - ``docs``
      - Builds the HTML documentation site.

docs/running/specialized-commands.rst

@@ -21,6 +21,25 @@ Important details:
 - ``--no-cache`` disables ``tmp/cache/phpunit``;
 - the packaged configuration registers the DevTools PHPUnit extension.
 
+``dependencies``
+----------------
+
+Analyzes missing and unused Composer dependencies.
+
+.. code-block:: bash
+
+   composer dependencies
+   vendor/bin/dev-tools dependencies
+
+Important details:
+
+- it requires ``shipmonk/composer-dependency-analyser`` and
+  ``icanhazstring/composer-unused`` to be installed in the target project;
+- it uses ``composer-dependency-analyser`` only for missing dependency checks
+  and leaves unused-package reporting to ``composer-unused``;
+- it returns a non-zero exit code when missing or unused dependencies are
+  found.
+
 ``code-style``
 --------------