fix(docs): reflow a wrapped code span so Mintlify parses the readiness doc

Docs Validation failed with `parsing error plans/gaia-agent-readiness.md:136:1
— Unexpected lazy line in expression in container`. Line 136 is only where the
list ends; the cause is three lines up. A code span containing `{export|import}`
wrapped across a line break inside a list item, so MDX opened a JS expression at
the `{` and ran past the end of the container looking for its close.

Reflowed so the span sits on one line. No wording changed.

Verified: `cd docs && npx mintlify@4.2.794 validate` passes, and reverting just
this reflow reproduces the identical 136:1 warning — so the fix is the one that
matters, not an incidental reformat.

Author: Ovtcharov

docs/plans/gaia-agent-readiness.md

@@ -129,9 +129,9 @@ unpick.
 - **`ToolRegistry` snapshot/restore** for #2800's rollback guarantee. Implied by #2800's acceptance
   criteria but not in its scope text.
 - **The naming decision.** #2804 says "settle the name in this issue, not at package time," and it
-  is still unsettled. `gaia-agent` collides conceptually with the existing `gaia agent
-  {export|import}` subcommand; `gaia-native` is the stated fallback. This is free to decide now
-  and expensive to change after packaging, signing, and eval baselines exist.
+  is still unsettled. `gaia-agent` collides conceptually with the existing
+  `gaia agent {export|import}` subcommand; `gaia-native` is the stated fallback. This is free to
+  decide now and expensive to change after packaging, signing, and eval baselines exist.
 
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