Rewrite renamed Jinja references anywhere inside {{ }} and {% %} delimiters

[Theater-ahyeon]

Description

Fixes #7559.

replace_jinja_reference() only matched the renamed identifier directly after {{, so after a sanitization-driven rename (invalid identifier or collision _2 suffix) every reference that wasn't at the head of an expression kept pointing at the old name:

• mid-expression uses like {{ current_index < max_attempts }} — the shape of a while-loop Condition;
• statement blocks like {% if my-block_output.success %} and {% for item in old_key %}, which the old pattern never matched at all.

With lax templating nothing errors — conditions evaluate against undefined or wrong values, so loops mis-terminate and guards mis-fire.

The function now matches the old identifier as a whole word (lookbehind + lookahead on identifier characters, so {{ old_key_extended }} and {{ other_key }} stay untouched) inside every {{ ... }} / {% ... %} segment, and skips quoted string literals so filter defaults like default('old_key') keep their values. The sentinel-based atomic rewrite in _rewrite_error_code_mapping_refs_atomic keeps working unchanged: sentinels are plain-string-replaced in the second phase and contain no identifier characters.

How Has This Been Tested?

• Extended the existing parametrized suite in tests/unit/test_workflow_parameter_validation.py with the issue's two reproductions (mid-expression {{ current_index < old_key }} and statement {% if old_key %}go{% endif %}), a {% for %} case, a quoted-literal case (default('old_key') keeps its value), and a statement partial-match case (other_old_key untouched).
• uv run pytest tests/unit/test_workflow_parameter_validation.py → 70 passed (63 pre-existing cases all still green, including the sentinel-driven sanitizer tests).
• Verified both reproductions from the issue now return the rewritten text, e.g. replace_jinja_reference("{{ current_index < max_attempts }}", "max_attempts", "max_attempts_2") → "{{ current_index < max_attempts_2 }}".
• ruff check clean on the touched files; ruff format applied.