fix(adapter-utils): provide a default author for local commits (#18094)

<!-- entire-trail-link-start -->
https://entire.com/gh/paperclipai/-/trails/209/changes/paperclip/209
<!-- entire-trail-link-end -->

## Thinking Path

> - Paperclip is the open source app people use to manage AI agents for
work.
> - Agents use managed launchers for Git and GitHub commands.
> - These launchers exclude host credentials and host Git identity.
> - A checkout without an author cannot save a local commit when managed
GitHub identity is absent.
> - A local author default belongs in the launcher that owns this
isolation.
> - This pull request supplies a private Paperclip default and preserves
explicit and managed identity selection.
> - Agents can save local work without manual author setup or extra
GitHub access.

## Linked Issues or Issue Description

**What happened?**

An ordinary `git commit` fails with `Author identity unknown` in a fresh
checkout without author settings or a usable managed GitHub identity. An
agent must set its own author to continue.

**Expected behavior**

The managed launcher supplies a default local author. Repository and
command settings override that default. A current managed identity
retains its existing precedence.

**Steps to reproduce**

Run the managed launcher in a fresh Git repository without author
settings or broker credentials. Add a file, then run `git commit -m
work`.

**Paperclip version or commit**

Reproduced at `063cfd43813cabf18417605fb9eefb9aacf95c8d` on Linux with
Node 25.9.0 and pnpm 9.15.4.

**Deployment mode**

Managed sandbox execution. The shared launcher also serves local and SSH
execution that selects managed access.

Related: #16662 changes precedence for a connected GitHub account. #8945
assigns identity to managed worktrees. This repair supplies the missing
anonymous launcher default and keeps the current managed precedence. It
does not require either change.

### Hypothesis and thesis for a fix

**Hypothesis:** The launcher removes inherited author variables and host
Git config. Without a broker identity or explicit repository settings,
it has no author. Four real-Git cases reproduce the reported error on
the base revision.

**Thesis for a fix:** Put `Paperclip <noreply@paperclip.ing>` in a
private Git config for each operation. Git treats it as global config,
so repository and command settings can override it. The existing broker
environment still takes precedence. Do not store a person's identity in
shared checkout config, where it could remain after steering or
revocation. The default grants no GitHub access.

## What Changed

- Write the default author to the existing private operation directory
with mode `0600`. Remove it when the operation exits.
- Point managed Git at this file while keeping host global/system
config, credentials and SSH identity excluded.
- Add real-Git regressions for missing, absent, unavailable and rejected
access. Preserve explicit overrides, identity changes and revocation
controls.
- Verify two shell commits through normal launcher staging and a commit
after anonymous heartbeat cleanup. Check saved files, commit metadata
and temporary config cleanup.
- Update identity documentation and the two run map recipes.

## Verification

- Red: the four new local-commit cases fail on the base launcher with
`Author identity unknown`.
- Green: all 80 focused tests pass in one run across
`github-launcher.test.ts`, `github-launcher-environment.test.ts`,
`heartbeat-github-launchers.test.ts` and `native-github-access.test.ts`
(23.31 seconds).
- A controlled filesystem failure first made the candidate discard valid
managed credentials. After the correction, the same real launcher
process retains them. Default-author file failure does not change
operation-directory readiness.
- Review found a second failure: a partial write can leave invalid Git
config. The real-process test failed before the repair with `fatal: bad
config line` from `git status`. The launcher now selects the default
file only after the write succeeds. Both write-failure cases retain
managed credentials, allow status, require identity when no default is
available, and save a commit with explicit identity. The test reads the
stored commit metadata with real Git.
- Real shells, generated launchers and Git create and inspect saved
commits. Sandbox transport and broker replies use controlled fixtures.
No live cloud rollout or GitHub write acceptance is claimed.
- The isolated test process excludes inherited task launcher paths, Git
config and broker authentication variables. An initial run exposed those
test-environment inputs; the isolated replay passed. The heartbeat
assertion now checks the private default file and its cleanup instead of
expecting `/dev/null`.
- Adapter-utils typecheck and build pass. Map validation and `git diff
--check` pass.
- Conflict repair on 2026-10-29: merged master
`fa5e70faf47ef2ca20bf2daf95b7503c94469b89` into the PR branch. Resolved
19 conflict paths by retaining master for unrelated files. All seven Git
identity files remain byte-for-byte equal to the reviewed fix. The final
diff is seven files, 145 additions and 15 deletions.
- At head `c501e3f28369d404c91082b89188dc150c9362a9`, all 80 focused
tests pass again (37.53 seconds). Adapter-utils typecheck and build
pass. Map validation and migration checks pass. The PR diff passes `git
diff --check`.
- Full workspace typecheck and build were attempted again. Both stop
because this sandbox has no Rust `cargo`. The duplicate full local
Vitest run was stopped after about five minutes without a final result
while full CI was running. The earlier full local attempt was stopped
without a final result. No local full-suite pass is claimed.
- GitHub now reports the PR as mergeable. All current-head checks have
completed. [Full CI run
40878973679](https://github.com/paperclipai/paperclip/actions/runs/40878973679)
passes, including typecheck, build, Rust, test shards and all eight E2E
shards. The exact-head check inventory has 54 successes, one neutral
Paperclip Review and two Storybook skips. Snyk passes. Greptile and
Paperclip each reviewed `c501e3f28369d404c91082b89188dc150c9362a9` at
5/5 with no actionable findings. All review threads are resolved. GitHub
reports the PR as clean and mergeable.
- The prior CI run had one failed E2E test: `a lost creation response
requires reload and cannot blindly replay commands`. Its YAML parser
received page text that starts with `Skip to Main Content`. The new run
passes E2E shard 7/8 and the full E2E gate. The prior failure remains
part of this record. A passing run does not establish the earlier
failure's cause. This change does not alter that test or the agent
configuration UI.

## Risks

- Commits without explicit or managed identity now use the generic
Paperclip author. Operators can still set repository or command
identity.
- `git config --global` writes to temporary operation config and does
not persist. The documentation states this behavior.
- If the private config directory cannot be prepared, commits still need
explicit identity. Existing redacted diagnostics and credential
isolation remain.
- One small synchronous file write is added to a directory the launcher
already creates. No new subprocess, network request, persistent identity
or authority cache is added.

> For core feature work, check [`ROADMAP.md`](ROADMAP.md) first and
discuss it in `#dev` before opening the PR. Feature PRs that overlap
with planned core work may need to be redirected — check the roadmap
first. See `CONTRIBUTING.md`.

## Model Used

OpenAI Codex, based on GPT-6, with reasoning, shell execution and tool
use. The runtime does not expose the exact model ID or context window
size to this agent.

## Checklist

- [x] I have included a thinking path that traces from project context
to this change
- [x] I have specified the model used (with version and capability
details)
- [x] I have checked ROADMAP.md and confirmed this PR does not duplicate
planned core work
- [x] I have searched GitHub for duplicate or related PRs and linked
them above
- [x] I have either (a) linked existing issues with `Fixes: #` / `Closes
#` / `Refs #` OR (b) described the issue in-PR following the relevant
issue template
- [x] I have not referenced internal/instance-local Paperclip issues or
links (only public GitHub `#NNN` / `github.com/paperclipai/paperclip`
URLs)
- [x] My branch name describes the change (e.g. `docs/...`, `fix/...`)
and contains no internal Paperclip ticket id or instance-derived details
- [x] I have run tests locally and they pass
- [x] I have added or updated tests where applicable
- [x] I have updated relevant documentation to reflect my changes
- [x] I have considered and documented any risks above
- [x] All Paperclip CI gates are green
- [x] Greptile is 5/5 with no open P2s, recommendations, or follow-ups
- [x] I will address all Greptile and reviewer comments before
requesting merge

---------

Co-authored-by: Paperclip <noreply@paperclip.ing>

maps/feature-map/runs-adapters.md

@@ -40,6 +40,17 @@ The agent header has one Run now action. Administrators can enable
 Capture raw provider traces under the agent configuration’s Debugging section
 for future runs. The header shows Raw tracing on while that setting is enabled.
 
+Managed Git launchers let agents save local commits without a GitHub connection
+or manual author setup. Verify a fresh checkout and a second shell in the same
+workspace: both commits should use `Paperclip <noreply@paperclip.ing>` when no
+identity is configured. Repository and command settings override this default;
+an eligible managed identity still takes precedence. Inspect stored commit
+metadata and confirm the default did not change repository or host configuration.
+Repeat with unavailable GitHub access; authenticated operations must still obey
+the existing credential checks. The [launcher controls](../../packages/adapter-utils/src/github-launcher.test.ts)
+and [real-shell staging controls](../../packages/adapter-utils/src/github-launcher-environment.test.ts)
+cover this local behavior, separately from live cloud execution and GitHub writes.
+
 For latency diagnosis with an operator OTLP endpoint, search the hashed run ID
 without restricting the root span name. Compare workspace preparation with its
 `workspace_<step>` intervals. Measure controller readiness separately through