fix: preserve ${VAR} env var references when writing config back to disk (#11560)

* fix: preserve ${VAR} env var references when writing config back to disk

Fixes #11466

When config is loaded, ${VAR} references are resolved to their plaintext
values. Previously, writeConfigFile would serialize the resolved values,
silently replacing "${ANTHROPIC_API_KEY}" with "sk-ant-api03-..." in the
config file.

Now writeConfigFile reads the current file pre-substitution, and for each
value that matches what a ${VAR} reference would resolve to, restores the
original reference. Values the caller intentionally changed are kept as-is.

This fixes all 50+ writeConfigFile call sites (doctor, configure wizard,
gateway config.set/apply/patch, plugins, hooks, etc.) without requiring
any caller changes.

New files:
- src/config/env-preserve.ts — restoreEnvVarRefs() utility
- src/config/env-preserve.test.ts — 11 unit tests

* fix: remove global config env snapshot race

* docs(changelog): note config env snapshot race fix

---------

Co-authored-by: Peter Steinberger <steipete@gmail.com>

CHANGELOG.md

@@ -69,6 +69,7 @@ Docs: https://docs.openclaw.ai
 - Signal/Install: auto-install `signal-cli` via Homebrew on non-x64 Linux architectures, avoiding x86_64 native binary `Exec format error` failures on arm64/arm hosts. (#15443) Thanks @jogvan-k.
 - Discord: avoid misrouting numeric guild allowlist entries to `/channels/<guildId>` by prefixing guild-only inputs with `guild:` during resolution. (#12326) Thanks @headswim.
 - Config: preserve `${VAR}` env references when writing config files so `openclaw config set/apply/patch` does not persist secrets to disk. Thanks @thewilloftheshadow.
+- Config: remove a cross-request env-snapshot race in config writes by carrying read-time env context into write calls per request, preserving `${VAR}` refs safely under concurrent gateway config mutations. (#11560) Thanks @akoscz.
 - Config: log overwrite audit entries (path, backup target, and hash transition) whenever an existing config file is replaced, improving traceability for unexpected config clobbers.
 - Process/Exec: avoid shell execution for `.exe` commands on Windows so env overrides work reliably in `runCommandWithTimeout`. Thanks @thewilloftheshadow.
 - Web tools/web_fetch: prefer `text/markdown` responses for Cloudflare Markdown for Agents, add `cf-markdown` extraction for markdown bodies, and redact fetched URLs in `x-markdown-tokens` debug logs to avoid leaking raw paths/query params. (#15376) Thanks @Yaxuan42.