#16922: fix: remove incorrect sandbox file tool guidance

## Summary Remove incorrect workspace guidance for sandboxed agents. Commit 2bf33077 added guidance stating file tools (read/write/edit/apply_patch) resolve paths against the host workspace. This is wrong — all file tools use `SandboxFsBridge` → `docker exec` inside the container. ## Changes - `src/agents/system-prompt.ts`: Remove sandbox-specific `workspaceGuidance` branch. Use the same guidance for both sandbox and non-sandbox modes. ## Evidence `SandboxFsBridgeImpl.runCommand` in `src/agents/sandbox/fs-bridge.ts` executes all file operations through `docker exec -i <containerName> sh -c <script>`. Host-side `node:fs` is never used when sandbox is enabled. ## Related - Closes #16920 - Related: #16790 (original sandbox path bug, fixed by 2bf33077) ✍️ Author: Claude Code with @carrotRakko (AI-written, human-approved) <!-- greptile_comment --> <h3>Greptile Summary</h3> This PR removes an incorrect sandbox-specific `workspaceGuidance` branch from the system prompt builder. The previous code told sandboxed agents that file tools (read/write/edit/apply_patch) resolve paths against the host workspace, which is wrong — `SandboxFsBridgeImpl.runCommand` in `src/agents/sandbox/fs-bridge.ts` runs all file operations via `docker exec` inside the container. The fix correctly unifies the guidance to use a single string for both sandbox and non-sandbox modes. - **Issue found**: The test in `src/agents/system-prompt.e2e.test.ts` (line 450-452) still asserts the old removed text (`"For read/write/edit/apply_patch, file paths resolve against host workspace: /tmp/openclaw."`) and will fail. This test needs to be updated to match the new behavior. <h3>Confidence Score: 3/5</h3> - The production code change is correct but the PR will break an existing e2e test. - The logic fix itself is sound and well-evidenced — sandbox file tools do use docker exec, not host-side node:fs. However, the corresponding e2e test in system-prompt.e2e.test.ts was not updated and will fail, which means CI should catch this. Score of 3 reflects that the code change is correct but incomplete. - src/agents/system-prompt.e2e.test.ts — contains a stale assertion (line 450-452) that will fail after this change. _{Last reviewed commit: 139c932} <!-- greptile_other_comments_section --> <!-- /greptile_comment -->