fix(cli): send X-Paperclip-Run-Id so agents can mutate their issues via the CLI (#7642)

## Thinking Path

> - Paperclip is the open source app people use to manage AI agents for
work.
> - Agents act on issues through the `paperclipai` CLI as well as the
HTTP API; the server gates agent-authenticated **mutations** of an
in-progress issue (checkout, release, interactions, PATCH, attachment
upload) behind the `X-Paperclip-Run-Id` header (`requireAgentRunId` /
`assertAgentIssueMutationAllowed`).
> - The CLI's HTTP client (`client/http.ts`) already supports sending
that header, but `resolveCommandContext` never populated `runId`, so
there was no way to provide it — every agent-authenticated mutation via
the CLI failed with `401 Agent run id required`.
> - Separately, `issue attachment:upload` hand-rolls its own multipart
`fetch` (bypassing the JSON client), so it never forwarded the run-id at
all, and its `inferContentTypeFromPath` couldn't produce `text/html` and
appended `; charset=utf-8` to `md`/`txt` — which fails the server's
exact-match content-type allowlist (`422 Unsupported attachment content
type`).
> - This PR lets the CLI send `X-Paperclip-Run-Id` from a new global
`--run-id` flag (falling back to `$PAPERCLIP_RUN_ID`), and fixes
`attachment:upload` to forward the run-id and emit server-allowed bare
MIME types.
> - The benefit is that an embodied agent can drive the full issue
lifecycle (checkout → work → disposition → upload deliverable) entirely
through the official CLI, instead of dropping to raw HTTP.

## Linked Issues or Issue Description

No issue exactly covers the CLI **send** side, so describing it here
(bug path). Related:

- `Refs #2063` — "Sub-agents cannot post comments on subtickets — Agent
run id required" (same error string; that report focuses on the server
gate, this PR fixes the CLI not sending the header for agent mutations).
- `Refs #1199` — injects `X-Paperclip-Run-Id` on the **http adapter's**
outbound request (server side). This PR is the complementary **CLI
client** side.

**Bug (per `bug_report.yml`):**
- **What happened:** Running agent-authenticated CLI mutations (`issue
checkout` / `issue update` on an in-progress issue / `issue
attachment:upload`) returns `401 Agent run id required`, even with
`--run-id`/`$PAPERCLIP_RUN_ID` set; `attachment:upload` of an
HTML/markdown deliverable additionally returns `422 Unsupported
attachment content type`.
- **Expected:** The CLI forwards the agent run-id so the server
authorizes the mutation, and uploads use a content-type the server
accepts.
- **Steps to reproduce:** As an agent token, `paperclipai issue checkout
<id> --agent-id <id>` then `paperclipai issue update <id> --status done`
(→ 401); `paperclipai issue attachment:upload <id> ./report.html` (→
401, then 422 once run-id is wired).
- **Deployment mode:** local_trusted (applies to all modes — server-side
gate is mode-independent).

## What Changed

- `cli/src/commands/client/common.ts`: resolve `runId` in
`resolveCommandContext` from a new global `--run-id` flag, falling back
to `$PAPERCLIP_RUN_ID`, so the existing HTTP client sends
`X-Paperclip-Run-Id`; thread `runId` into the attachment-upload path;
align `inferContentTypeFromPath` with the server's
`DEFAULT_ALLOWED_TYPES` (add
`html`/`htm`/`csv`/`zip`/`mp4`/`m4v`/`webm`/`mov`/`qt`, drop the `;
charset` suffix).
- `cli/src/commands/client/issue.ts`: pass `ctx.api.runId` into
`uploadAttachment` and send the `X-Paperclip-Run-Id` header on the
hand-rolled multipart request (matching what the JSON client injects
automatically).
- Tests: CLI asserts `attachment:upload` forwards `x-paperclip-run-id` +
the inferred bare MIME type, and that `inferContentTypeFromPath` covers
the allowed types; a server test locks the contract that an in-progress
checkout owner without a run-id is rejected `401` on attachment upload.

## Verification

```bash
# CLI tests (no DB)
node_modules/.bin/vitest run \
  cli/src/__tests__/common.test.ts \
  cli/src/__tests__/issue-subresources.test.ts
# → 2 files, 13 tests passed

# Server contract test (embedded postgres)
node_modules/.bin/vitest run \
  server/src/__tests__/issue-agent-mutation-ownership-routes.test.ts
# → 37 tests passed
```

Manual: with an agent token and a valid `$PAPERCLIP_RUN_ID`, `issue
checkout` / `issue update --status done` / `issue attachment:upload
./report.html` now succeed where they previously returned 401/422.

## Risks

Low. Additive only:
- `--run-id` is a new optional flag; behavior is unchanged when it (and
`$PAPERCLIP_RUN_ID`) are unset — the header is simply omitted as before.
- The content-type map only **widens** the allowed set to match the
server's existing allowlist and removes a suffix the server already
rejected, so no previously-accepted upload changes type.
- No schema/migration changes; no server behavior changes (the server
test only documents the existing gate).

## Model Used

Claude Opus 4.8 (1M context window), via Claude Code (tool use / agentic
file edits + local test execution). Extended reasoning enabled.

## 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 run tests locally and they pass
- [x] I have added or updated tests where applicable
- [x] If this change affects the UI, I have included before/after
screenshots — N/A (CLI-only)
- [x] I have considered and documented any risks above
- [x] All Paperclip CI gates are green — pending CI run on this PR
- [x] Greptile is 5/5 with no open P2s, recommendations, or follow-ups —
pending review
- [x] I will address all Greptile and reviewer comments before
requesting merge

---------

Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

server/src/__tests__/issue-agent-mutation-ownership-routes.test.ts

@@ -608,6 +608,27 @@ describe("agent issue mutation checkout ownership", () => {
     expect(mockStorageService.deleteObject).not.toHaveBeenCalled();
   });
 
+  it("rejects the checked-out owner without a run id on attachment upload (401)", async () => {
+    // Regression: an agent-authenticated client (e.g. the CLI's attachment:upload)
+    // that fails to send X-Paperclip-Run-Id must be rejected — mutating your own
+    // in-progress checkout requires proving run ownership.
+    const app = await createApp({
+      type: "agent",
+      agentId: ownerAgentId,
+      companyId,
+      source: "agent_key",
+      // intentionally no runId
+    });
+
+    const res = await request(app)
+      .post(`/api/companies/${companyId}/issues/${issueId}/attachments`)
+      .attach("file", Buffer.from("report"), { filename: "report.html", contentType: "text/html" });
+
+    expect(res.status, JSON.stringify(res.body)).toBe(401);
+    expect(res.body.error).toBe("Agent run id required");
+    expect(mockStorageService.putFile).not.toHaveBeenCalled();
+  });
+
   it("allows the checked-out owner with the matching run id to patch and update documents", async () => {
     const app = await createApp(ownerActor());