Refine default exclude list: keep .docker config, add never-backup paths

Removed /.docker (small, contains registry auth config worth keeping)
and /Library/Parallels (small app support; the actual VM disks live in
~/Parallels) from the default excludes.

Added recommended excludes for data that should never be backed up:
- Language/toolchain caches (npm, cargo, rustup, go modules, maven,
  vagrant boxes, node_modules, __pycache__, .venv)
- VM disk images (Parallels, VMware Fusion, VirtualBox, OrbStack, UTM)
- Downloaded LLM models (ollama, LM Studio)
- Cloud-synced storage (~/Library/CloudStorage, iCloud Drive) — synced
  elsewhere, and dataless placeholder files would be force-downloaded
- Android SDK and emulator images

internal/cli/init.go

@@ -49,7 +49,6 @@ snapshots:
       - "/.cpan/build"
       - "/.cpan/sources"
       - "/.gradle/caches"
-      - "/.docker"
       - "/.dropbox"
       - "/.minikube/cache"
       - "/.local/share/containers/podman/machine"
@@ -62,11 +61,38 @@ snapshots:
       - "/Library/PubSub"
       - "/Library/Homebrew"
       - "/Library/Developer"
-      - "/Library/Parallels"
       - "/Library/Google/GoogleSoftwareUpdate"
       - "/Library/Preferences/Macromedia/Flash Player"
       - "/Library/Preferences/SDMHelpData"
       - "/Library/VoiceTrigger/SAT"
+      # Language/toolchain package caches (rebuildable from registries)
+      - "/.npm"
+      - "/.cargo/registry"
+      - "/.cargo/git"
+      - "/.rustup/toolchains"
+      - "/go/pkg/mod"
+      - "/.m2/repository"
+      - "/.vagrant.d/boxes"
+      - "node_modules"
+      - "__pycache__"
+      - ".venv"
+      # Virtual machine disk images (huge; remove these lines to back them up)
+      - "/Parallels"
+      - "/Virtual Machines.localized"
+      - "/VirtualBox VMs"
+      - "/.orbstack"
+      - "/Library/Containers/com.utmapp.UTM"
+      # Downloaded LLM models (huge, re-downloadable)
+      - "/.ollama/models"
+      - "/.lmstudio/models"
+      # Cloud-synced storage. These are synced to a provider already, and on
+      # modern macOS may contain dataless placeholder files that the backup
+      # would force-download in full.
+      - "/Library/CloudStorage"
+      - "/Library/Mobile Documents"
+      # Android SDK and emulator images (re-downloadable)
+      - "/Library/Android/sdk"
+      - "/.android/avd"
       # Cloud-synced or restorable-from-server data
       - "/Library/Mail"
       - "/Library/Mail Downloads"