docs: drop ring buffer mentions from ws spec and plan

Co-Authored-By: Claude <noreply@anthropic.com>

docs/superpowers/plans/2026-07-03-terminal-websocket.md

@@ -12,7 +12,7 @@
 
 **Decisions (from spec, confirmed):**
 - WebSocket library: `gorilla/websocket`
-- Replay buffer: not in v1 (deferred; ring buffer is implemented but not exposed)
+- Replay buffer: not in v1 (deferred; a future task can add it behind a separate accessor)
 - Reconnect: up to 3 attempts with exponential backoff on transport error; never on exit banner
 
 ## File Structure Map
@@ -88,7 +88,7 @@
   2. Modify internal/process/session.go: add Stdin io.WriteCloser, Subscribers []Subscription, Exit process.ExitInfo (Code int, Signal string), mu sync.Mutex. Use a slice, not a map.
   3. Modify internal/process/manager.go:
      - In LocalManager.Start: open a pipe for cmd.Stdin, capture the write end. Open a pipe for cmd.Stdout AND cmd.Stderr, point both at the same reader, capture the reader.
-     - Spawn goroutine A: read from the merged pipe in a 4 KiB loop, append to a 64 KiB ring buffer (truncate oldest when full, do not expose the buffer in this task), and for each Subscription in session.Subscribers do a non-blocking send (select with default that drops the chunk). Stop when the pipe returns EOF.
+     - Spawn goroutine A: read from the merged pipe in a 4 KiB loop, and for each Subscription in session.Subscribers do a non-blocking send (select with default that drops the chunk). Stop when the pipe returns EOF. No replay buffer in v1.
      - Spawn goroutine B: call cmd.Wait(), populate session.Exit (use ProcessState.ExitCode() and Sys().(syscall.WaitStatus).Signal() if signal), then close every Subscription's channel exactly once. Do not delete the session from the map.
      - Add LocalManager.Subscribe(workspaceID) (Subscription, error): if no session, return util.New(util.CodeNotFound, "no running process"). Allocate a channel, append a subscription backed by it, return it.
   4. Keep existing tests compiling. New Subscribe method is additive.
@@ -472,7 +472,7 @@ Reconnect: 1s, 2s, 4s backoff. Stop after 3 failed attempts → "error". Reset o
 - Process model grows `Subscribe` and `Stdin`: Tasks 1, 2.
 - 409 when process not running: Task 3.
 - Exit banner on close: Task 3.
-- Replay buffer: explicitly deferred (Task 1 implements it but does not expose it).
+- Replay buffer: not in v1. The manager's reader goroutine reads and fans out directly; no history is kept.
 - Frontend hook with reconnect policy: Task 4.
 - TerminalPanel wired to live process: Task 5.
 - Backward compatibility: existing routes unchanged, Manager interface is additively grown, no wire format changes.