restore hook/result durationMs — review keeps wall-clock audit timing durable

Reverses item 3 of the tighten-hook-protocol-contract RFC per review:
a persistence log is written for future readers, and hook wall-clock
runtime is audit signal (which hook made a turn slow). runHook keeps
its injected now clock and RunHookResult wrapper, the bridges pass the
measured duration through HookResultRecord, the snapshot normalizer
keeps its replay scrub, and the hook fixtures carry the field again.
The RFC records the reversal; the other three prunes stand.

packages/hooks/hook-protocol/README.md

@@ -9,7 +9,7 @@ Why a shared lib at all: Codex deliberately reimplements a *subset* of the Claud
 | Concern | Here (`dsh-hook-protocol`) | The bridge (`dsh-hooks-claude` / `-codex`) |
 |---|---|---|
 | Matcher test | `matchesMatcher(pattern, query, mode)` — literal-or-regex by `mode` | picks its `mode` (`claude` = literal-or-regex, `codex` = always regex) |
-| Run a hook | `runHook(bash, hook, opts)` — stdin payload + env via `ctx.bash`, decode | builds the per-event stdin **payload** + the dialect's **env** |
+| Run a hook | `runHook(bash, hook, opts, now)` — stdin payload + env via `ctx.bash`, decode | builds the per-event stdin **payload** + the dialect's **env** |
 | Decode output | `parseHookOutput(exit, stdout, stderr)` → neutral `HookOutput` | maps the neutral `HookOutput` onto a seam-specific typed Decision |
 | Merge N hooks | `mergeHookOutputs(outputs)` → most-restrictive `MergedHookOutcome` | — |
 | Durable record | `appendHookInvoked` / `appendHookResult` (`hook/*` session events; the result's `decision`/`stderrSummary` derive from the `HookOutput` here) | calls them around each invocation |
@@ -17,7 +17,7 @@ Why a shared lib at all: Codex deliberately reimplements a *subset* of the Claud
 ## Primitives
 
 - **`matchesMatcher(matcher, query, mode)`** — match-all on absent/`''`/`'*'`; `claude` mode treats a pure `[A-Za-z0-9_|]+` pattern as a literal (pipe = exact-match alternation) and anything else as a regex; `codex` mode is always an unanchored regex. An invalid regex matches nothing (never throws).
-- **`runHook(bash, hook, options)`** — serialize `options.payload` to the hook's stdin (with a trailing newline iff `options.trailingNewline`), merge `options.env` after the executor's credential scrub (the `dsh-bash` trusted-plugin surface), honor the hook's `timeoutSec` (else `options.defaultTimeoutMs` — the bridge owns the default, its config defaulting to the lib's `DEFAULT_HOOK_TIMEOUT_MS` 10-minute reference), and decode the result (threading `options.expectedEventName` to the codec). Never throws: an executor rejection (infra fault) becomes a `HookOutput` with `exitCode: undefined` (a non-blocking error).
+- **`runHook(bash, hook, options, now)`** — serialize `options.payload` to the hook's stdin (with a trailing newline iff `options.trailingNewline`), merge `options.env` after the executor's credential scrub (the `dsh-bash` trusted-plugin surface), honor the hook's `timeoutSec` (else `options.defaultTimeoutMs` — the bridge owns the default, its config defaulting to the lib's `DEFAULT_HOOK_TIMEOUT_MS` 10-minute reference), and decode the result (threading `options.expectedEventName` to the codec). Never throws: an executor rejection (infra fault) becomes a `HookOutput` with `exitCode: undefined` (a non-blocking error). `now` is injected for testable durations.
 - **`parseHookOutput(exitCode, stdout, stderr, expectedEventName?)`** — the exit-code + structured-stdout codec. Exit `0` → parse JSON stdout (lenient: non-JSON is left for the bridge); exit `2` → blocking error, `stderr` is the block reason (surfaced as `decision: 'block'`); other → non-blocking error. `hookSpecificOutput.permissionDecision` (allow/deny/ask) overrides a legacy top-level `decision`; `additionalContext`/`updatedInput`/`systemMessage`/`continue`/`stopReason` are parsed too. The schemas key the `hookSpecificOutput` block by `hookEventName`, so passing `expectedEventName` (the firing event) DISCARDS a block whose `hookEventName` names a different event — or omits it entirely — its event-scoped fields don't take effect (a `PreToolUse` block on a `Stop` hook is malformed, and so is a discriminator-less block that would otherwise apply to any event), while the event-agnostic top-level fields still apply. Pure and total.
 - **`mergeHookOutputs(outputs)`** — fold the results of every hook that matched one point: permission precedence **deny > ask > allow**, halt sticky on the first `continue:false`, block reasons joined with `\n\n`, `additionalContext`/`systemMessages` accumulated in order.
 
@@ -26,7 +26,7 @@ Why a shared lib at all: Codex deliberately reimplements a *subset* of the Claud
 Declaration-merged into `SessionEventMap` (log-only, like `compact/*` — NOT a `SurfaceEventType`, no `surfaceOp`):
 
 - `hook/invoked` — `{ turn, point, dialect, matcher?, handlerId }`: a hook command ran.
-- `hook/result` — `{ turn, point, handlerId, decision, exitCode?, stderrSummary? }`: its outcome, paired by `handlerId`. `appendHookResult` owns the semantics: `decision` is the hook's parsed decision, else `'stop'` on `continue:false`, else `'pass'`; `stderrSummary` is the trimmed stderr truncated to the record's `stderrSummaryMaxChars` (the bridge's config, reference default `DEFAULT_STDERR_SUMMARY_MAX_CHARS` = 500; omitted when empty).
+- `hook/result` — `{ turn, point, handlerId, decision, exitCode?, stderrSummary?, durationMs }`: its outcome, paired by `handlerId`. `appendHookResult` owns the semantics: `decision` is the hook's parsed decision, else `'stop'` on `continue:false`, else `'pass'`; `stderrSummary` is the trimmed stderr truncated to the record's `stderrSummaryMaxChars` (the bridge's config, reference default `DEFAULT_STDERR_SUMMARY_MAX_CHARS` = 500; omitted when empty).
 
 Like every event they must sit inside an open turn. The mid-turn points (`PreToolUse`/`PostToolUse`/`UserPromptSubmit`/`Stop`) fire inside the loop's open turn by construction; `SessionStart` gets no `hook/*` record (its injected `context/message` is the durable evidence) — see the hooks RFC.