fix(worktree): track explicit remote-only branch (#31645)

* fix(worktree): track explicit remote branch

* test(worktree): cover remote branch path retry

* fix(worktree): resolve cached remote branches canonically

* fix(git): retain commit validation in bounded ref probes

* fix(worktree): preserve selected remote identity during creation

* test(worktree): count cached resolver Git work during path retries

* Fix branch intent state in composer source fixture

* Make Git and daemon regression fixtures portable

* Use the selected base for existing branch creation

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Co-authored-by: Brennan Benson <79079362+brennanb2025@users.noreply.github.com>

src/shared/worktree/create-types.ts

@@ -97,6 +97,8 @@ export type CreateWorktreeArgs = {
   compareBaseRef?: string
   /** Existing local branches may contain slashes that the filesystem-safe worktree name cannot. */
   branchNameOverride?: string
+  /** Only an explicit existing-branch pick opts out of new-branch allocation. */
+  branchIntent?: 'open-existing'
   setupDecision?: SetupDecision
   /** Per-create choice; omitted callers use the execution host's saved default. */
   setupOnly?: boolean