Add orca-replay skill

plugins/all-skills/skills/orca-replay/SKILL.md

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+---
+name: orca-replay
+category: development
+description: Answers questions about a past agent run from its recording rather than from memory, and replays or forks that run. Use when asked why an earlier run did something, or to reproduce a failure.
+---
+
+# OrcaReplay Run Reader
+
+Coding agents are confidently wrong about their own history. A summary written from memory is
+missing the tool results, the exit codes, and the files that changed without anyone mentioning
+them.
+
+This skill enforces one rule: **when a question is about something that already happened, read the
+trace before answering.** Do not reconstruct it. If a recording exists, guessing is the wrong move
+even when the guess would have been right.
+
+## When to Use This Skill
+
+- "Why did you delete / overwrite / move X?"
+- "What changed this file?" or "Which step broke the build?"
+- "Can you reproduce yesterday's failure?"
+- "Would a different model have got this right?"
+
+## What This Skill Does
+
+1. **Finds the run** — `orca_list_runs`, newest first, naming the run each fork came from.
+2. **Narrows to the cause** — `orca_graph` with `to: <event seq>` returns only the chain that
+   produced one event. That is the shape of an answer to *why*; the full timeline
+   (`orca_show_run`) is the shape of an answer to *what*.
+3. **Separates evidence from inference** — every edge is labelled `recorded` (the recorder watched
+   it happen) or `inferred` (derived just now from a named rule). "The trace shows the `rm` at step
+   14 removed it" and "this looks like the `rm` at step 14, going by timing" are different claims,
+   and collapsing them into one confident sentence is the exact failure this skill exists to
+   prevent.
+4. **Reproduces before explaining** — `orca_replay` re-runs the recording offline and reports what
+   could not be reproduced.
+5. **Compares models only when asked** — `orca_compare` forks one run onto several models from the
+   same checkpoint, graded by a shell command whose exit code is the verdict.
+
+## How to Use
+
+### Basic Usage
+
+```
+Why did the last run overwrite src/config.ts?
+```
+
+The agent reads the trace instead of recalling the session, and answers from the tool call that
+did it.
+
+```
+Does yesterday's failure still reproduce?
+```
+
+## Example
+
+**User**: "Which step broke the build?"
+
+**Output**:
+```
+Step 14 did. From the recording (recorded edge, not inferred):
+
+  14  TOOL   file_editor   {"command":"str_replace","path":".../tsconfig.json"}
+  15  SHELL  npm run build  exit 2
+  16  FILE   tsconfig.json  modified +1 -1
+
+The edit at 14 removed "strict": true, and the build at 15 exited 2. I replayed the run
+(reused=5/5, divergences=0) and it fails the same way.
+```
+
+## Tips
+
+- **Pass `worktree: true` to replay.** Without it, replay restores the recorded filesystem over the
+  working tree for the duration of the run, so uncommitted work is absent in the meantime — and
+  stays absent if the replay is interrupted.
+- **Check what re-executes before the first replay.** Replay serves the model's answers from the
+  trace, but the agent process runs again for real, so its shell commands run again too. A run that
+  only read files and edited the repository is free to replay; one that touched Docker, a database
+  or a remote host is not.
+- **Replay is not a sandbox.** It blocks provider egress, not the network.
+- **A matching replay is not a determinism result.** The model is not re-asked, its recorded
+  answers are served back — so replay cannot tell you whether a *fresh* run would fail the same
+  way. Say so rather than implying it did.
+- **`reused=3/5` is usually not a failure.** Harnesses make calls for themselves — a quota probe, a
+  session-naming request — and replay does not repeat them.
+- **No recording means no answer.** Say that plainly and offer to start one with
+  `orca record claude`, rather than falling back to a reconstruction.
+
+## Requirements
+
+The `orcareplay` npm package (Node 20+) with its MCP server registered as `orca`, and at least one
+recorded run in the project's `.orca/runs` directory. Apache-2.0 —
+[Continuum-AI-Corp/OrcaReplay](https://github.com/Continuum-AI-Corp/OrcaReplay).