new: added exception notification feature

[sttk]

This PR adds an exception notification feature to this package.
When a Err object is instantiated, it notifies pre-registered exception handlers.
To enable this notification feature, the system property github.sttk.errs.notify=true must be specified at program startup.

[Copilot]

Pull Request Overview

This PR introduces an exception notification feature for the package, enabling pre-registered exception handlers to be notified upon the creation of an exception object. Key changes include:

• Updated test expectations for exception line numbers in ExcTest.java.
• Added a new exception handler interface (ExcHandler.java) and its supporting functionality in Exc.java.
• Introduced new tests (ExcHandlerTest.java) and updated related module and package configuration files.

Reviewed Changes

Copilot reviewed 6 out of 7 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
src/test/java/com/github/sttk/errs/ExcTest.java	Updated expected line numbers in assertions to match new behavior.
src/test/java/com/github/sttk/errs/ExcHandlerTest.java	Added tests to validate synchronous and asynchronous exception notification.
src/main/java/module-info.java	Added a dependency on java.management to support notification features.
src/main/java/com/github/sttk/errs/package-info.java	Adjusted header formatting in the file comments.
src/main/java/com/github/sttk/errs/ExcHandler.java	Introduced a new functional interface for exception handling.
src/main/java/com/github/sttk/errs/Exc.java	Implemented exception notification logic with handler registration and management.

Files not reviewed (1)

• pom.xml: Language not supported

Comments suppressed due to low confidence (1)

src/main/java/com/github/sttk/errs/Exc.java:223

• [nitpick] Consider renaming 'isFixed' to a more descriptive name such as 'handlersFixed' to better convey that it prevents further additions of handlers.

private static boolean isFixed = false;

[Copilot]

Pull Request Overview

This PR introduces an exception notification feature that informs pre-registered exception handlers when an exception (Exc) is instantiated. Key changes include:

• Updating test expectations for the exception’s file and line details.
• Adding new APIs for registering synchronous and asynchronous exception handlers.
• Integrating a notification mechanism into the Exc constructors and wiring it through a system property.

Reviewed Changes

Copilot reviewed 6 out of 7 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
src/test/java/com/github/sttk/errs/ExcTest.java	Adjusted expected line numbers in tests to match updated stack trace details.
src/test/java/com/github/sttk/errs/ExcHandlerTest.java	Added tests to verify addition, fixing, and notification of exception handlers.
src/main/java/module-info.java	Added a requirement for java.management to support the new notification feature.
src/main/java/com/github/sttk/errs/package-info.java	Reformatted comment lines.
src/main/java/com/github/sttk/errs/ExcHandler.java	Introduces the functional interface for exception handling.
src/main/java/com/github/sttk/errs/Exc.java	Enhanced to notify handlers on creation and added new methods for handler management.

Files not reviewed (1)

• pom.xml: Language not supported

Comments suppressed due to low confidence (2)

src/test/java/com/github/sttk/errs/ExcTest.java:182

• Verify that the exception message’s file and line details (now updated to line 180) correctly mirror the actual stack trace position after changes in the constructor.

assertThat(exc.toString()).isEqualTo("com.github.sttk.errs.Exc { reason = com.github.sttk.errs.ExcTest$IndexOutOfRange { name=data, index=4, min=0, max=3 }, file = ExcTest.java, line = 180 }");

src/test/java/com/github/sttk/errs/ExcTest.java:190

• Ensure that the expected exception message now showing line 188 (for the cause case) correctly reflects the updated behavior.

assertThat(exc.toString()).isEqualTo("com.github.sttk.errs.Exc { reason = com.github.sttk.errs.ExcTest$IndexOutOfRange { name=data, index=4, min=0, max=3 }, file = ExcTest.java, line = 188, cause = java.lang.IndexOutOfBoundsException: Index out of range: 4 }");