Implement complete CLI commands for MVP-1 Personal Tracker

- Refactored CLI commands from nested Typer subapps to direct command functions
- Fixed main.py to use app.command() instead of app.add_typer_command()
- Fixed project_service.py to properly load projects from YAML
- Fixed file_storage.py to save session JSON files alongside markdown
- Added missing methods: write_file, read_file, extract_autogen_section, get_recent_sessions
- Fixed root_path and repo_path to use strings instead of Path objects

tracker/storage/file_storage.py

@@ -1,6 +1,7 @@
 """Storage layer for file-based persistence."""
 
 import json
+from datetime import datetime
 from pathlib import Path
 from typing import Optional
 
@@ -117,22 +118,34 @@ class FileStorage:
             f.write(new_content)
 
     def write_session_file(self, session: Session) -> None:
-        """Crea projects/<slug>/sessions/YYYY-MM-DD_HHMM.md"""
+        """Crea projects/<slug>/sessions/YYYY-MM-DD_HHMM.md y el JSON correspondiente."""
         from tracker.storage.markdown_writer import MarkdownWriter
 
         sessions_path = self._sessions_path(session.project_slug)
         sessions_path.mkdir(parents=True, exist_ok=True)
 
         started = session.started_at
-        filename = started.strftime("%Y-%m-%d_%H%M.md")
-        session_path = sessions_path / filename
+        md_filename = started.strftime("%Y-%m-%d_%H%M.md")
+        json_filename = f"{session.id}.json"
 
+        # Write markdown file
         writer = MarkdownWriter()
         content = writer.format_session_file(session)
-
-        with open(session_path, "w", encoding="utf-8") as f:
+        md_path = sessions_path / md_filename
+        with open(md_path, "w", encoding="utf-8") as f:
             f.write(content)
 
+        # Write JSON file for tracking
+        json_path = sessions_path / json_filename
+        session_data = session.model_dump(mode="json")
+        # Serialize datetime objects to ISO format
+        if isinstance(session_data.get("started_at"), datetime):
+            session_data["started_at"] = session_data["started_at"].isoformat()
+        if isinstance(session_data.get("ended_at"), datetime):
+            session_data["ended_at"] = session_data["ended_at"].isoformat()
+        with open(json_path, "w", encoding="utf-8") as f:
+            json.dump(session_data, f, indent=2, ensure_ascii=False, default=str)
+
     def active_session_path(self) -> Path:
         """Returns Path to projects/.active_session.json"""
         return self.projects_root / ".active_session.json"
@@ -156,3 +169,98 @@ class FileStorage:
         path = self.active_session_path()
         if path.exists():
             path.unlink()
+
+    def write_file(self, slug: str, relative_path: str, content: str) -> None:
+        """Escribe contenido a un archivo en el proyecto.
+
+        Args:
+            slug: Project slug.
+            relative_path: Relative path within the project.
+            content: Content to write.
+        """
+        file_path = self._project_path(slug) / relative_path
+        file_path.parent.mkdir(parents=True, exist_ok=True)
+        with open(file_path, "w", encoding="utf-8") as f:
+            f.write(content)
+
+    def read_file(self, slug: str, relative_path: str) -> str:
+        """Lee contenido de un archivo en el proyecto.
+
+        Args:
+            slug: Project slug.
+            relative_path: Relative path within the project.
+
+        Returns:
+            File content or empty string if not found.
+        """
+        file_path = self._project_path(slug) / relative_path
+        if not file_path.exists():
+            return ""
+        with open(file_path, "r", encoding="utf-8") as f:
+            return f.read()
+
+    def extract_autogen_section(self, slug: str, section: str) -> str:
+        """Extrae contenido de una seccion AUTOGEN del README.md.
+
+        Args:
+            slug: Project slug.
+            section: Section name (e.g., "SESSIONS", "NEXT_STEPS").
+
+        Returns:
+            Content between AUTOGEN markers, or empty string if not found.
+        """
+        from tracker.storage.markdown_reader import MarkdownReader
+        reader = MarkdownReader()
+        content = self.read_readme(slug)
+        return reader.extract_autogen_section(content, section)
+
+    def get_recent_sessions(self, slug: str, limit: int = 5) -> list:
+        """Obtiene las sesiones mas recientes de un proyecto.
+
+        Args:
+            slug: Project slug.
+            limit: Maximum number of sessions to return.
+
+        Returns:
+            List of Session objects sorted by date (most recent first).
+        """
+        from tracker.models.session import Session
+
+        sessions_path = self._sessions_path(slug)
+        if not sessions_path.exists():
+            return []
+
+        sessions = []
+        for json_file in sessions_path.glob("*.json"):
+            try:
+                with open(json_file, "r", encoding="utf-8") as f:
+                    data = json.load(f)
+                session = Session(**data)
+                sessions.append(session)
+            except (json.JSONDecodeError, TypeError):
+                continue
+
+        # Sort by started_at descending
+        sessions.sort(key=lambda s: s.started_at, reverse=True)
+        return sessions[:limit]
+
+    def list_projects(self) -> list[str]:
+        """Lista todos los slugs de proyectos.
+
+        Returns:
+            List of project slugs.
+        """
+        if not self.projects_root.exists():
+            return []
+        return [d.name for d in self.projects_root.iterdir() if d.is_dir() and not d.name.startswith(".")]
+
+    def project_exists(self, slug: str) -> bool:
+        """Verifica si un proyecto existe.
+
+        Args:
+            slug: Project slug.
+
+        Returns:
+            True if project exists.
+        """
+        return self._project_path(slug).exists()