COMMIT_MESS

fix(tor): spec compliance - rename VirtualPort, remove SetEnabled, fix logs

Per AI.md PART 32 Tor hidden service spec:

- Rename HiddenServicePort → VirtualPort with yaml:"virtual_port" in
  TorConfig (config.go and all references in tor.go, tor_test.go,
  config.go defaults, config_test.go)
- Remove SetEnabled() method — spec explicitly says no enable/disable
  toggle; Tor is auto-enabled when binary is found at runtime
- Fix success log format to "Tor: {address}" (was "[Tor] Hidden service:
  ... (port X → Y)")
- Remove conf.ControlSocket usage — bine's StartConf has no such field;
  bine uses TCP control port auto-assigned by Tor
- Remove platform-specific control socket branching (runtime.GOOS check)
- Fix torrc persistence: create-only on first run (os.Stat check), never
  overwrite on start; permissions enforced (0600) on existing file
- Add MaxStreamsPerCircuit to torrc generation in getTorConfig()
- Update tests: replace TestTorServiceSetEnabled / TestTorServiceSetEnabledFalse
  with equivalent Stop() idempotency tests

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>