feat: add 4 new crates (queue, tracing, http, cli) + enhancements to existing crates

New crates:
- mytheclipse-queue: unified job queue with WorkerPool, retry/backoff, DLQ
  Backends: in-memory (default), Redis, NATS, PostgreSQL
- mytheclipse-tracing: tracing subscriber layers with env filter + OTLP/Jaeger export
- mytheclipse-http: HTTP client/server with timeout + tracing, axum server
- mytheclipse-cli: CLI framework with clap derive, built-in subcommands

Enhancements to existing crates:
- mytheclipse-core: SemaphorePool, LeaderElection, HealthRegistry/HealthCheck
- mytheclipse-cache: AutoRefreshCache (bg refresh on miss), CacheMetrics
- mytheclipse-config: ConfigSchema for JSON Schema generation
- mytheclipse-storage: MultipartUploadDriver trait
- mytheclipse-crypto: PASETO v4.local token support

All features compile with --all-features; tests + clippy pass clean.

crates/mytheclipse-cache/src/metrics.rs

@@ -0,0 +1,59 @@
+//! Cache instrumentation metrics (hit/miss/eviction counters).
+
+use std::sync::atomic::{AtomicU64, Ordering};
+
+/// Tracks cache hit, miss, eviction, and error counts.
+#[derive(Default)]
+pub struct CacheMetrics {
+    hits: AtomicU64,
+    misses: AtomicU64,
+    evictions: AtomicU64,
+    errors: AtomicU64,
+}
+
+impl CacheMetrics {
+    pub fn new() -> Self {
+        Self::default()
+    }
+
+    pub fn hit(&self) {
+        self.hits.fetch_add(1, Ordering::Relaxed);
+    }
+
+    pub fn miss(&self) {
+        self.misses.fetch_add(1, Ordering::Relaxed);
+    }
+
+    pub fn eviction(&self) {
+        self.evictions.fetch_add(1, Ordering::Relaxed);
+    }
+
+    pub fn error(&self) {
+        self.errors.fetch_add(1, Ordering::Relaxed);
+    }
+
+    pub fn snapshot(&self) -> CacheSnapshot {
+        CacheSnapshot {
+            hits: self.hits.load(Ordering::Relaxed),
+            misses: self.misses.load(Ordering::Relaxed),
+            evictions: self.evictions.load(Ordering::Relaxed),
+            errors: self.errors.load(Ordering::Relaxed),
+        }
+    }
+}
+
+/// A point-in-time read of cache metrics.
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub struct CacheSnapshot {
+    pub hits: u64,
+    pub misses: u64,
+    pub evictions: u64,
+    pub errors: u64,
+}
+
+impl CacheSnapshot {
+    pub fn hit_rate(&self) -> f64 {
+        let total = self.hits + self.misses;
+        if total == 0 { 0.0 } else { self.hits as f64 / total as f64 }
+    }
+}