feat(logging): add crash logging and improve log management

- Add panic hook to capture crash info to ~/.cc-switch/crash.log
  - Records timestamp, app version, OS/arch, thread info
  - Full stack trace with force_capture for release builds
  - Safe error handling (no nested panics)

- Enable logging for both Debug and Release builds
  - Info level for all builds
  - Output to console and ~/.cc-switch/logs/
  - 5MB max file size with rotation

- Add log cleanup on startup
  - Keep only 2 most recent log files
  - Works on all platforms

- Change panic strategy from "abort" to "unwind"
  - Required for backtrace capture in release builds

src-tauri/Cargo.toml

@@ -77,7 +77,8 @@ objc2-app-kit = { version = "0.2", features = ["NSColor"] }
 codegen-units = 1
 lto = "thin"
 opt-level = "s"
-panic = "abort"
+# 使用 unwind 以便 panic hook 能捕获 backtrace（abort 会直接终止无法捕获）
+panic = "unwind"
 strip = "symbols"
 
 [dev-dependencies]