v0.6.0

Compatibility with opencode2 v2.0.27's built-in worktree tools (PR
anomalyco/opencode#53981), which moved worktree_create, worktree_list,
and worktree_remove into the host.

• Native creates produce cow clones. The built-in create carries no
  strategy field and uses the location's default strategy, which this plugin
  registers. Verified on 2.7.50: strategy-less creates report cow in the
  inventory and materialize Deep clones, including when the create is the
  server's first worktree call — no lazy-activation gap. The new native-path
  matrix (scripts/e2e/native-matrix.ts, 18 checks) pins the contract.
• remove_worktree now requires edit approval (permission: "edit",
  the host's removal convention since v2.0.27). With edit: deny the tool
  is hidden, same as the built-in remover.
• The strategy's force-less refusal reason carries through the native remove
  path verbatim, and force: true discards ignored files on both surfaces.
  Cow clones hold env files and local state that exist nowhere else, so
  treat force on a cow lane as destructive.
• Suite: 348 tests; the e2e harness (112 checks) and the native-path matrix
  (18 checks) pass against opencode2 2.7.50.