fix: guard resolveUserPath against undefined input (#10176)

* fix: guard resolveUserPath against undefined input

When subagent spawner omits workspaceDir, resolveUserPath receives
undefined and crashes on .trim().  Add a falsy guard that falls back
to process.cwd(), matching the behavior callers already expect.

Closes #10089

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* fix: harden runner workspace fallback (#10176) (thanks @Yida-Dev)

* fix: harden workspace fallback scoping (#10176) (thanks @Yida-Dev)

* refactor: centralize workspace fallback classification and redaction (#10176) (thanks @Yida-Dev)

* test: remove explicit any from utils mock (#10176) (thanks @Yida-Dev)

* security: reject malformed agent session keys for workspace resolution (#10176) (thanks @Yida-Dev)

---------

Co-authored-by: Yida-Dev <reyifeijun@gmail.com>
Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>
Co-authored-by: Gustavo Madeira Santana <gumadeiras@gmail.com>

CHANGELOG.md

@@ -38,6 +38,7 @@ Docs: https://docs.openclaw.ai
 - Control UI: add hardened fallback for asset resolution in global npm installs. (#4855) Thanks @anapivirtua.
 - Update: remove dead restore control-ui step that failed on gitignored dist/ output.
 - Update: avoid wiping prebuilt Control UI assets during dev auto-builds (`tsdown --no-clean`), run update doctor via `openclaw.mjs`, and auto-restore missing UI assets after doctor. (#10146) Thanks @gumadeiras.
+- Agents: harden embedded and CLI runner workspace resolution for missing/blank runtime inputs by falling back to per-agent workspace defaults (not CWD), preventing `sessions_spawn` early crashes. (#10176) Thanks @Yida-Dev.
 - Models: add forward-compat fallback for `openai-codex/gpt-5.3-codex` when model registry hasn't discovered it yet. (#9989) Thanks @w1kke.
 - Auto-reply/Docs: normalize `extra-high` (and spaced variants) to `xhigh` for Codex thinking levels, and align Codex 5.3 FAQ examples. (#9976) Thanks @slonce70.
 - Compaction: remove orphaned `tool_result` messages during history pruning to prevent session corruption from aborted tool calls. (#9868, fixes #9769, #9724, #9672)