regex: bound RE2 compilation memory during matcher initialization

[Naveed8951]

Commit Message:
regex: bound RE2 compilation memory during matcher initialization

Additional Description:
Bound RE2 compilation memory up-front using explicit re2::RE2::Options derived
from existing Envoy max program size limits, preventing excessive resource usage
during regex compilation.

Risk Level:
Medium

Testing:

• Build and compile targets including source/common/common/regex.cc
• Manual verification by loading configs with large/complex regex patterns and
  observing bounded compilation behavior

Docs Changes:
None

Release Notes:
None

Platform Specific Features:
None

[repokitteh-read-only]

Hi @Naveed8951, welcome and thank you for your contribution.

We will try to review your Pull Request as quickly as possible.

In the meantime, please take a look at the contribution guidelines if you have not done so already.

🐱

Caused by: #42924 was opened by Naveed8951.

see: more, trace.