feat: add ~100 new achievements for extended gameplay

Add extensive new achievement system covering:
- Extended token/code/file/message milestones
- Tool mastery achievements (Edit, Write, Glob, Task, WebFetch, MCP)
- Daily streaks (week, two-week, month, quarter)
- Time-based achievements (morning, night, lunch, coffee break)
- Day-specific achievements (Monday, Wednesday, Friday, weekend)
- Special day achievements (New Year, Valentine's, Halloween, Christmas, Leap Day)
- Message content achievements (long messages, markdown, code blocks)
- Emotional achievements (frustrated, excited, confused, curious, impressed)
- Programming language achievements (Rust, Python, JS, TS, Go, C++, Java, etc.)
- Project type achievements (frontend, backend, config, docs)
- Refactoring/testing/documentation achievements
- Completion percentage achievements (50%, 75%, 100%)

Also adds streak tracking infrastructure to stats:
- Session counting
- Consecutive day tracking
- Morning/night session tracking
- Total days used tracking

src-tauri/src/stats.rs

@@ -1,4 +1,5 @@
 use crate::achievements::{check_achievements, AchievementProgress};
+use chrono::{Local, Timelike};
 use serde::{Deserialize, Serialize};
 use std::collections::HashMap;
 use std::time::Instant;
@@ -28,6 +29,14 @@ pub struct UsageStats {
     #[serde(skip)]
     pub session_start: Option<Instant>,
 
+    // Extended tracking for achievements
+    pub sessions_started: u64,
+    pub consecutive_days: u64,
+    pub total_days_used: u64,
+    pub morning_sessions: u64, // Sessions started before 9 AM
+    pub night_sessions: u64,   // Sessions started after 10 PM
+    pub last_session_date: Option<String>, // ISO date string for streak tracking
+
     // Achievement tracking
     #[serde(skip)]
     pub achievements: AchievementProgress,
@@ -65,6 +74,47 @@ impl UsageStats {
         self.session_duration_seconds = 0;
         self.session_start = Some(Instant::now());
         self.achievements.start_session();
+
+        // Track session start for achievements
+        self.track_session_start();
+    }
+
+    pub fn track_session_start(&mut self) {
+        let now = Local::now();
+        let today = now.format("%Y-%m-%d").to_string();
+        let hour = now.hour();
+
+        // Increment session count
+        self.sessions_started += 1;
+
+        // Track morning/night sessions
+        if hour < 9 {
+            self.morning_sessions += 1;
+        }
+        if hour >= 22 {
+            self.night_sessions += 1;
+        }
+
+        // Track consecutive days and total days
+        if let Some(last_date) = &self.last_session_date {
+            if last_date != &today {
+                // Check if it's the next day (consecutive)
+                if is_consecutive_day(last_date, &today) {
+                    self.consecutive_days += 1;
+                } else {
+                    // Streak broken
+                    self.consecutive_days = 1;
+                }
+                self.total_days_used += 1;
+                self.last_session_date = Some(today);
+            }
+            // Same day - don't increment anything
+        } else {
+            // First session ever
+            self.consecutive_days = 1;
+            self.total_days_used = 1;
+            self.last_session_date = Some(today);
+        }
     }
 
     pub fn increment_messages(&mut self) {
@@ -127,12 +177,34 @@ impl UsageStats {
             session_tools_usage: self.session_tools_usage.clone(),
             session_duration_seconds: self.session_duration_seconds,
             session_start: self.session_start,
+            sessions_started: self.sessions_started,
+            consecutive_days: self.consecutive_days,
+            total_days_used: self.total_days_used,
+            morning_sessions: self.morning_sessions,
+            night_sessions: self.night_sessions,
+            last_session_date: self.last_session_date.clone(),
             achievements: AchievementProgress::new(), // Dummy for copy
         };
         check_achievements(&stats_copy, &mut self.achievements)
     }
 }
 
+// Helper function to check if two dates are consecutive
+fn is_consecutive_day(prev_date: &str, current_date: &str) -> bool {
+    use chrono::NaiveDate;
+
+    let prev = NaiveDate::parse_from_str(prev_date, "%Y-%m-%d").ok();
+    let current = NaiveDate::parse_from_str(current_date, "%Y-%m-%d").ok();
+
+    match (prev, current) {
+        (Some(p), Some(c)) => {
+            let diff = c.signed_duration_since(p).num_days();
+            diff == 1
+        }
+        _ => false,
+    }
+}
+
 // Pricing as of January 2025
 // https://www.anthropic.com/pricing
 fn calculate_cost(input_tokens: u64, output_tokens: u64, model: &str) -> f64 {