fix: align linear token sequence semantics

[jbachorik]

Summary

• aligns Linear Token Sequence \s and \S handling with default JDK whitespace semantics
• makes the bracket-tail shortcut require the literal-space delimiters it recognizes
• restricts wildcard LTS admission to globally DOTALL patterns, preserving default-dot semantics
• adds JDK differential and adversarial regression coverage

Validation

• `./gradlew jacocoVerify build`
• focused LTS and categorizer tests after final cleanup
• final implementation-plan validation and code review run independently

Stacked on #112 (which is stacked on #111).

[Copilot]

Pull request overview

This PR tightens and aligns the Linear Token Sequence (LTS) fast-path semantics with the intended Java/JDK regex behavior by (a) matching JDK-style whitespace for \s/\S, (b) making the bracket-tail shortcut enforce the literal-space delimiters it recognizes, and (c) preventing LTS admission of wildcard-dot patterns unless the pattern is globally DOTALL.

Changes:

• Align LTS whitespace/non-whitespace classification with JDK-style whitespace (and add JDK-differential regression coverage).
• Require literal spaces around the bracket-tail shortcut and add adversarial coverage.
• Refuse LTS routing for default-dot wildcard patterns (only allow wildcard LTS when globally DOTALL).

Reviewed changes

Copilot reviewed 7 out of 7 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
reggie-runtime/src/test/java/com/datadoghq/reggie/runtime/LinearTokenSequenceMatcherTest.java	Adds JDK-differential tests for whitespace semantics, bracket-tail delimiter strictness, and DOTALL/default-dot routing.
reggie-runtime/src/main/java/com/datadoghq/reggie/runtime/RuntimeCompiler.java	Tightens LTS admission rules around wildcard-dot usage and DOTALL requirements.
reggie-runtime/src/main/java/com/datadoghq/reggie/runtime/LinearTokenSequenceMatcher.java	Updates LTS whitespace handling and enforces literal-space delimiters for the bracket-tail shortcut; adds SKIP_ANY_EXCEPT_NEWLINE execution path.
reggie-codegen/src/test/java/com/datadoghq/reggie/codegen/analysis/PatternCategorizerTest.java	Updates categorizer fixture to explicitly be DOTALL for bracket-tail shortcut eligibility.
reggie-codegen/src/main/java/com/datadoghq/reggie/codegen/analysis/PatternCategorizer.java	Splits dotall vs default-dot wildcard categorization; requires DOTALL .* for bracket-tail shortcut detection.
reggie-codegen/src/main/java/com/datadoghq/reggie/codegen/analysis/PatternAtom.java	Introduces ANY_STAR_EXCEPT_NEWLINE atom kind.
reggie-codegen/src/main/java/com/datadoghq/reggie/codegen/analysis/LinearTokenSequencePlan.java	Adds SKIP_ANY_EXCEPT_NEWLINE op kind and mapping from the new atom kind.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

[chatgpt-codex-connector]

💡 Codex Review

Here are some automated review suggestions for this pull request.

Reviewed commit: a87ffa492c

ℹ️ About Codex in GitHub

Your team has set up Codex to review pull requests in this repo. Reviews are triggered when you

• Open a pull request for review
• Mark a draft as ready
• Comment "@codex review".

If Codex has suggestions, it will comment; otherwise it will react with 👍.

Codex can also answer questions or update the PR. Try commenting "@codex address that feedback".

[codecov-commenter]

Codecov Report

❌ Patch coverage is 68.88889% with 14 lines in your changes missing coverage. Please review.
✅ Project coverage is 84.4%. Comparing base (44e3604) to head (81f6dc5).

Files with missing lines	Patch %	Lines
...hq/reggie/codegen/analysis/PatternCategorizer.java	50.0%	0 Missing and 5 partials ⚠️
.../com/datadoghq/reggie/runtime/RuntimeCompiler.java	50.0%	1 Missing and 4 partials ⚠️
...ghq/reggie/runtime/LinearTokenSequenceMatcher.java	81.8%	0 Missing and 4 partials ⚠️

Additional details and impacted files

@@                    Coverage Diff                    @@
##             agent/logs-reggie-l1b    #113     +/-   ##
=========================================================
- Coverage                     84.4%   84.4%   -0.1%     
  Complexity                       1       1             
=========================================================
  Files                          147     147             
  Lines                        42991   42993      +2     
  Branches                      5859    5860      +1     
=========================================================
  Hits                         36296   36296             
- Misses                        4906    4911      +5     
+ Partials                      1789    1786      -3     

Files with missing lines	Coverage Δ
...ggie/codegen/analysis/LinearTokenSequencePlan.java	82.0% <100.0%> (-0.6%)	⬇️
...datadoghq/reggie/codegen/analysis/PatternAtom.java	87.5% <100.0%> (+0.4%)	⬆️
...ghq/reggie/runtime/LinearTokenSequenceMatcher.java	80.6% <81.8%> (+0.6%)	⬆️
...hq/reggie/codegen/analysis/PatternCategorizer.java	59.3% <50.0%> (-0.1%)	⬇️
.../com/datadoghq/reggie/runtime/RuntimeCompiler.java	87.9% <50.0%> (-0.4%)	⬇️

---

Continue to review full report in Codecov by Harness.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 44e3604...81f6dc5. Read the comment docs.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.