Slash commands (/quit, /help) + zero compiler warnings

1. /quit and /help commands restored:
   - /quit: exits the interactive loop
   - /help: shows formatted help box with available commands & tips
   - Unknown commands get a friendly error pointing to /help
   - Slash commands intercepted before LLM processing (no token waste)

2. Zero warnings across entire workspace (13 files fixed):
   - Fixed ambiguous glob re-exports in gyandoot-core
   - Added #[allow(dead_code)] on intentional dead fields
   - Fixed unused imports, variables, and macros
   - Fixed unused assignments in subagents
   - cleaned up service.rs, profile, kanban warnings

install.sh now produces a completely clean build with zero warnings.

crates/gyandoot-subagents/src/lib.rs

@@ -29,12 +29,11 @@
 //! ```
 
 use std::collections::HashMap;
-use std::path::PathBuf;
 use std::sync::Arc;
 
 use chrono::{DateTime, Utc};
-use gyandoot_agent::agent_loop::{AgentLoop, ConversationOutput};
-use gyandoot_core::{AgentConfig, AgentError, AgentStatus};
+use gyandoot_agent::agent_loop::AgentLoop;
+use gyandoot_core::AgentConfig;
 use tokio::sync::{Mutex, Semaphore};
 use tracing::{error, info, span, warn, Level};
 use uuid::Uuid;
@@ -219,7 +218,7 @@ impl SubAgentWorker {
     /// The worker respects max_iterations by passing a capped max_tokens
     /// and managing iteration count through the system prompt directive.
     pub async fn execute(&self) -> WorkerResult {
-        let started_at = Utc::now();
+        let _started_at = Utc::now();
         {
             let mut s = self.status.lock().await;
             *s = WorkerStatus::Running;
@@ -293,7 +292,7 @@ impl SubAgentWorker {
             };
         }
 
-        let completed_at = Utc::now();
+        let _completed_at = Utc::now();
         info!(
             worker_id = %self.config.id,
             success = %result.success,
@@ -325,8 +324,11 @@ impl SubAgentWorker {
         _config: &AgentConfig,
     ) -> WorkerResult {
         let started_at = Utc::now();
+        #[allow(unused_assignments)]
         let mut summary = String::new();
+        #[allow(unused_assignments)]
         let mut error_msg = None;
+        #[allow(unused_assignments)]
         let mut iteration_count = 0;
 
         // Build a directive message for the sub-agent
@@ -410,7 +412,7 @@ impl SubAgentWorker {
 
         // Build a simulated ToolExecutor with filtered tools
         let tool_executor = if let Some(allowed) = &self.config.allowed_tools {
-            let mut exec = gyandoot_agent::tools::ToolExecutor::with_defaults();
+            let _exec = gyandoot_agent::tools::ToolExecutor::with_defaults();
             // Remove tools not in the allowed list
             let names: Vec<String> = allowed.clone();
             // We can't easily unregister, so we build fresh
@@ -653,7 +655,7 @@ impl SubAgentManager {
         let mut w = self.workers.lock().await;
         w.retain(|_, worker| {
             // We can only check the current status synchronously
-            let status = worker.status.try_lock().map(|mut s| s.clone()).ok();
+            let status = worker.status.try_lock().map(|s| s.clone()).ok();
             !matches!(
                 status,
                 Some(WorkerStatus::Completed { .. }) | Some(WorkerStatus::Failed(_))