feat: enhance agent personality, tool guidance, and memory hygiene

- Expand communication style presets (professional, expressive, custom)
- Enrich SOUL.md with human-like tone and emoji-awareness guidance
- Add crash recovery and sub-task scoping guidance to AGENTS.md scaffold
- Add 'Use when / Don't use when' guidance to TOOLS.md and runtime prompts
- Implement memory hygiene system with configurable archiving and retention
- Add MemoryConfig options: hygiene_enabled, archive_after_days, purge_after_days, conversation_retention_days
- Archive old daily memory and session files to archive subdirectories
- Purge old archives and prune stale SQLite conversation rows
- Add comprehensive tests for new features

src/doctor/mod.rs

@@ -0,0 +1,123 @@
+use crate::config::Config;
+use anyhow::{Context, Result};
+use chrono::{DateTime, Utc};
+
+const DAEMON_STALE_SECONDS: i64 = 30;
+const SCHEDULER_STALE_SECONDS: i64 = 120;
+const CHANNEL_STALE_SECONDS: i64 = 300;
+
+pub fn run(config: &Config) -> Result<()> {
+    let state_file = crate::daemon::state_file_path(config);
+    if !state_file.exists() {
+        println!("🩺 ZeroClaw Doctor");
+        println!("  ❌ daemon state file not found: {}", state_file.display());
+        println!("  💡 Start daemon with: zeroclaw daemon");
+        return Ok(());
+    }
+
+    let raw = std::fs::read_to_string(&state_file)
+        .with_context(|| format!("Failed to read {}", state_file.display()))?;
+    let snapshot: serde_json::Value = serde_json::from_str(&raw)
+        .with_context(|| format!("Failed to parse {}", state_file.display()))?;
+
+    println!("🩺 ZeroClaw Doctor");
+    println!("  State file: {}", state_file.display());
+
+    let updated_at = snapshot
+        .get("updated_at")
+        .and_then(serde_json::Value::as_str)
+        .unwrap_or("");
+
+    if let Ok(ts) = DateTime::parse_from_rfc3339(updated_at) {
+        let age = Utc::now()
+            .signed_duration_since(ts.with_timezone(&Utc))
+            .num_seconds();
+        if age <= DAEMON_STALE_SECONDS {
+            println!("  ✅ daemon heartbeat fresh ({age}s ago)");
+        } else {
+            println!("  ❌ daemon heartbeat stale ({age}s ago)");
+        }
+    } else {
+        println!("  ❌ invalid daemon timestamp: {updated_at}");
+    }
+
+    let mut channel_count = 0_u32;
+    let mut stale_channels = 0_u32;
+
+    if let Some(components) = snapshot
+        .get("components")
+        .and_then(serde_json::Value::as_object)
+    {
+        if let Some(scheduler) = components.get("scheduler") {
+            let scheduler_ok = scheduler
+                .get("status")
+                .and_then(serde_json::Value::as_str)
+                .map(|s| s == "ok")
+                .unwrap_or(false);
+
+            let scheduler_last_ok = scheduler
+                .get("last_ok")
+                .and_then(serde_json::Value::as_str)
+                .and_then(parse_rfc3339)
+                .map(|dt| Utc::now().signed_duration_since(dt).num_seconds())
+                .unwrap_or(i64::MAX);
+
+            if scheduler_ok && scheduler_last_ok <= SCHEDULER_STALE_SECONDS {
+                println!(
+                    "  ✅ scheduler healthy (last ok {}s ago)",
+                    scheduler_last_ok
+                );
+            } else {
+                println!(
+                    "  ❌ scheduler unhealthy/stale (status_ok={}, age={}s)",
+                    scheduler_ok, scheduler_last_ok
+                );
+            }
+        } else {
+            println!("  ❌ scheduler component missing");
+        }
+
+        for (name, component) in components {
+            if !name.starts_with("channel:") {
+                continue;
+            }
+
+            channel_count += 1;
+            let status_ok = component
+                .get("status")
+                .and_then(serde_json::Value::as_str)
+                .map(|s| s == "ok")
+                .unwrap_or(false);
+            let age = component
+                .get("last_ok")
+                .and_then(serde_json::Value::as_str)
+                .and_then(parse_rfc3339)
+                .map(|dt| Utc::now().signed_duration_since(dt).num_seconds())
+                .unwrap_or(i64::MAX);
+
+            if status_ok && age <= CHANNEL_STALE_SECONDS {
+                println!("  ✅ {name} fresh (last ok {age}s ago)");
+            } else {
+                stale_channels += 1;
+                println!("  ❌ {name} stale/unhealthy (status_ok={status_ok}, age={age}s)");
+            }
+        }
+    }
+
+    if channel_count == 0 {
+        println!("  ℹ️ no channel components tracked in state yet");
+    } else {
+        println!(
+            "  Channel summary: {} total, {} stale",
+            channel_count, stale_channels
+        );
+    }
+
+    Ok(())
+}
+
+fn parse_rfc3339(raw: &str) -> Option<DateTime<Utc>> {
+    DateTime::parse_from_rfc3339(raw)
+        .ok()
+        .map(|dt| dt.with_timezone(&Utc))
+}