Fix regex combination issue

[rdettai-sk]

Description

Got

regex_res: Err(
    Error {
        context: "failed to build combined regex automaton during warmup for field `_dynamic` (path: `process\u{1}executable\0s`, 6 patterns)",
        source: TooManyStates(
            1000,
        ),
    },

How was this PR tested?

Describe how you tested this PR.

[Copilot]

Pull request overview

This PR updates the ES compatibility REST API scenario for regex/wildcard matching, aiming to reproduce (and guard against) failures when building a combined automaton from multiple patterns across several fields.

Changes:

• Comments out the existing regexp-focused scenario steps in 0031-regex.yaml.
• Adds a new active scenario step containing a deeply nested bool query with many wildcard clauses (case-insensitive) across multiple fields, expecting 0 hits (and implicitly requiring the query to be accepted without error).

---

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[Copilot]

Pull request overview

Copilot reviewed 9 out of 10 changed files in this pull request and generated 1 comment.

Comments suppressed due to low confidence (1)

quickwit/rest-api-tests/scenarii/es_compatibility/0031-regex.yaml:16

• This scenario file previously contained multiple regex-related test cases, but they are now entirely commented out. That effectively drops coverage for the original regexp behaviors (basic match, anchoring behavior, case_insensitive, anchors escaping, query_string regex) and makes the file only exercise the new wildcard-heavy query.

Instead of commenting out the earlier scenarios, they should stay active and the new reproduction should be added as an additional YAML document (separated by ---).

# Basic regex match
params:
  size: 0
json:
  track_total_hits: true
  query:
    regexp:
      type:
        value: ".*event"
expected:
  hits:
    total:
      value: 100
      relation: "eq"
---
# Regex always match from start to end (`(re)` equivalent to `^(re)$`)