docs(code-runtime-python): register the pythonBin load-rejection change; harden PYABS

The review's follow-ups: (1) the product-visible change (an unresolvable
basename pythonBin now fails at load instead of a run-time ENOENT worker-exit)
is registered in the settlement note, paired. (2) PYABS falls back to the bare
name when python3 is not resolvable, instead of interpolating the literal
'undefined' into the wrappers.

.agents/notes/implemented/bug-fix/2026-07-31-code-runtime-python-settlement-fixes.i18n.yaml

@@ -2,5 +2,5 @@
 # side as of the last confirmed-consistent state. Both languages carry equal authority;
 # after editing either side, bring the other along and re-record with:
 #   pnpm run verify-translation-pairing --write .agents/notes/implemented/bug-fix/2026-07-31-code-runtime-python-settlement-fixes.md
-2026-07-31-code-runtime-python-settlement-fixes.md: 33c0495fba322a9bc5545c1cdddd3df23d2f8df4
-2026-07-31-code-runtime-python-settlement-fixes.zh.md: 522f23ceba03440204e0f5b71334599434caa0b8
+2026-07-31-code-runtime-python-settlement-fixes.md: f485f28e12dbffd386fd57755d657252dfed5daf
+2026-07-31-code-runtime-python-settlement-fixes.zh.md: 5a6b8673ce313516ada5900a910dd15d126c1af3

packages/code-runtime/code-runtime-python/tests/runtime.spec.ts

@@ -14,7 +14,7 @@ import type { Config } from '../src/index.ts'
 // interpreters only reachable through the caller's PATH (Nix, pyenv). Baking
 // the resolved absolute path mirrors what resolvePythonBin does for the product
 // spawn.
-const PYABS = resolvePythonBin('python3')
+const PYABS = resolvePythonBin('python3') ?? 'python3'
 import type { CodeBindingFunction, CodeJsonValue, CodeRunResult } from '@deepseek-ai/dsh-code-runtime'
 
 /**