fix(security): [HIGH] resolve Denial of Service (DoS) vulnerability

[Tugamer89]

Severity: HIGH

Vulnerability: The application was susceptible to Denial of Service (DoS) and memory exhaustion because there was no upper limit on the number of states that could be added to a finite automaton during its construction.

Impact: A malicious actor or an excessively complex programmatic input could continually add states to the builder, eventually causing an OutOfMemoryError, which would crash the application or service hosting the engine.

Fix: Introduced a MAX_STATES limit of 10,000 in AbstractAutomatonBuilder.java. The addState method now checks if this limit has been reached and throws an IllegalStateException with a descriptive, secure error message before allocating the new state.

Verification: Ran mvn clean test to ensure all existing tests pass. Added a new unit test, testMaxStatesDoSPrevention in AbstractAutomatonBuilderTest.java, which explicitly attempts to add 10,001 states and successfully asserts that the expected IllegalStateException is thrown on the 10,001st addition. Formatted code with mvn spotless:apply.

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PR created automatically by Jules for task 10761521994817724456 started by @Tugamer89

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[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
100.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud