add context window monitor

Writes the current context window to logs/current_context_window (uses a symlink to a session ID).

This PR was unfortunately generated by a different LLM and did a ton of superficial reformating, it's actually a fairly small and benign change, but I don't want to roll back everything. Hope that's ok.

crates/g3-core/src/project.rs

@@ -7,19 +7,19 @@ use std::path::{Path, PathBuf};
 pub struct Project {
     /// The workspace directory for the project
     pub workspace_dir: PathBuf,
-    
+
     /// Path to the requirements document (for autonomous mode)
     pub requirements_path: Option<PathBuf>,
-    
+
     /// Override requirements text (takes precedence over requirements_path)
     pub requirements_text: Option<String>,
-    
+
     /// Whether the project is in autonomous mode
     pub autonomous: bool,
-    
+
     /// Project name (derived from workspace directory name)
     pub name: String,
-    
+
     /// Session ID for tracking
     pub session_id: Option<String>,
 }
@@ -32,7 +32,7 @@ impl Project {
             .and_then(|n| n.to_str())
             .unwrap_or("unnamed")
             .to_string();
-        
+
         Self {
             workspace_dir,
             requirements_path: None,
@@ -42,33 +42,36 @@ impl Project {
             session_id: None,
         }
     }
-    
+
     /// Create a project for autonomous mode
     pub fn new_autonomous(workspace_dir: PathBuf) -> Result<Self> {
         let mut project = Self::new(workspace_dir.clone());
         project.autonomous = true;
-        
+
         // Look for requirements.md in the workspace directory
         let requirements_path = workspace_dir.join("requirements.md");
         if requirements_path.exists() {
             project.requirements_path = Some(requirements_path);
         }
-        
+
         Ok(project)
     }
-    
+
     /// Create a project for autonomous mode with requirements text override
-    pub fn new_autonomous_with_requirements(workspace_dir: PathBuf, requirements_text: String) -> Result<Self> {
+    pub fn new_autonomous_with_requirements(
+        workspace_dir: PathBuf,
+        requirements_text: String,
+    ) -> Result<Self> {
         let mut project = Self::new(workspace_dir.clone());
         project.autonomous = true;
         project.requirements_text = Some(requirements_text);
-        
+
         // Don't look for requirements.md file when text is provided
         // The text override takes precedence
-        
+
         Ok(project)
     }
-    
+
     /// Set the workspace directory and update related paths
     pub fn set_workspace(&mut self, workspace_dir: PathBuf) {
         self.workspace_dir = workspace_dir.clone();
@@ -77,7 +80,7 @@ impl Project {
             .and_then(|n| n.to_str())
             .unwrap_or("unnamed")
             .to_string();
-        
+
         // Update requirements path if in autonomous mode
         if self.autonomous {
             let requirements_path = workspace_dir.join("requirements.md");
@@ -86,18 +89,18 @@ impl Project {
             }
         }
     }
-    
+
     /// Get the workspace directory
     pub fn workspace(&self) -> &Path {
         &self.workspace_dir
     }
-    
+
     /// Check if requirements file exists
     pub fn has_requirements(&self) -> bool {
         // Has requirements if either text override is provided or requirements file exists
         self.requirements_text.is_some() || self.requirements_path.is_some()
     }
-    
+
     /// Read the requirements file content
     pub fn read_requirements(&self) -> Result<Option<String>> {
         // Prioritize requirements text override
@@ -110,7 +113,7 @@ impl Project {
             Ok(None)
         }
     }
-    
+
     /// Create the workspace directory if it doesn't exist
     pub fn ensure_workspace_exists(&self) -> Result<()> {
         if !self.workspace_dir.exists() {
@@ -118,18 +121,18 @@ impl Project {
         }
         Ok(())
     }
-    
+
     /// Change to the workspace directory
     pub fn enter_workspace(&self) -> Result<()> {
         std::env::set_current_dir(&self.workspace_dir)?;
         Ok(())
     }
-    
+
     /// Get the logs directory for the project
     pub fn logs_dir(&self) -> PathBuf {
         self.workspace_dir.join("logs")
     }
-    
+
     /// Ensure the logs directory exists
     pub fn ensure_logs_dir(&self) -> Result<()> {
         let logs_dir = self.logs_dir();