fix #1252: Add predictable naming to tasks instead of UUIDs

[ricardozanini]

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What this PR does / why we need it:
Fixes #1252

Special notes for reviewers:

Additional information (if needed):

[Copilot]

Pull request overview

Updates the Java fluent DSL to generate deterministic task names when callers pass null/blank names (and when using name-less overloads), replacing previously random UUID-based naming to improve debuggability and testability (Issue #1252).

Changes:

• Replace UUID defaults in fluent SPI convenience overloads with null so builders can apply deterministic naming.
• Implement deterministic auto-naming in task list builders via a taskType-index scheme.
• Add a new JUnit test suite covering auto-naming across top-level and nested task builders (try/forEach/fork).

Reviewed changes

Copilot reviewed 19 out of 19 changed files in this pull request and generated 6 comments.

Show a summary per file

File	Description
fluent/spec/src/test/java/io/serverlessworkflow/fluent/spec/TaskItemDefaultNamingTest.java	Adds unit tests asserting deterministic default naming for unnamed tasks (including nested builders).
fluent/spec/src/main/java/io/serverlessworkflow/fluent/spec/spi/TryCatchFluent.java	Changes default overload to pass null (enabling deterministic naming downstream).
fluent/spec/src/main/java/io/serverlessworkflow/fluent/spec/spi/SwitchTaskFluent.java	Changes default overload to pass null for switch item names.
fluent/spec/src/main/java/io/serverlessworkflow/fluent/spec/spi/SwitchFluent.java	Changes default overload to pass null (enabling deterministic naming downstream).
fluent/spec/src/main/java/io/serverlessworkflow/fluent/spec/spi/SetFluent.java	Changes default overloads to pass null (enabling deterministic naming downstream).
fluent/spec/src/main/java/io/serverlessworkflow/fluent/spec/spi/RaiseFluent.java	Changes default overload to pass null (enabling deterministic naming downstream).
fluent/spec/src/main/java/io/serverlessworkflow/fluent/spec/spi/ListenFluent.java	Changes default overload to pass null (enabling deterministic naming downstream).
fluent/spec/src/main/java/io/serverlessworkflow/fluent/spec/spi/ForkFluent.java	Changes default overload to pass null (enabling deterministic naming downstream).
fluent/spec/src/main/java/io/serverlessworkflow/fluent/spec/spi/ForEachFluent.java	Changes default overload to pass null (enabling deterministic naming downstream).
fluent/spec/src/main/java/io/serverlessworkflow/fluent/spec/spi/EmitFluent.java	Changes default overload to pass null (enabling deterministic naming downstream).
fluent/spec/src/main/java/io/serverlessworkflow/fluent/spec/spi/CallOpenAPIFluent.java	Changes default overload to pass null (enabling deterministic naming downstream).
fluent/spec/src/main/java/io/serverlessworkflow/fluent/spec/spi/CallHttpFluent.java	Changes default overload to pass null (enabling deterministic naming downstream).
fluent/spec/src/main/java/io/serverlessworkflow/fluent/spec/TaskItemListBuilder.java	Plumbs task type into default-name helper for each task kind.
fluent/spec/src/main/java/io/serverlessworkflow/fluent/spec/BaseTaskItemListBuilder.java	Introduces deterministic naming helper (taskType + "-" + list.size()) and task type constants.
experimental/fluent/func/src/main/java/io/serverlessworkflow/fluent/func/spi/CallFnFluent.java	Changes default overload to pass null (enabling deterministic naming downstream).
experimental/fluent/func/src/main/java/io/serverlessworkflow/fluent/func/FuncTaskItemListBuilder.java	Updates func DSL list builder to use deterministic naming helper (adds TYPE_FUNCTION).
experimental/fluent/func/src/main/java/io/serverlessworkflow/fluent/func/FuncSwitchTaskBuilder.java	Adds deterministic naming for onPredicate(...) when name is null/blank.
experimental/fluent/func/src/main/java/io/serverlessworkflow/fluent/func/FuncForkTaskBuilder.java	Adds deterministic naming for unnamed fork branches.
experimental/fluent/func/src/main/java/io/serverlessworkflow/fluent/func/FuncForTaskBuilder.java	Adds deterministic naming for unnamed loop tasks.

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[Copilot]

Pull request overview

Copilot reviewed 20 out of 20 changed files in this pull request and generated 5 comments.

Comments suppressed due to low confidence (1)

experimental/fluent/func/src/main/java/io/serverlessworkflow/fluent/func/FuncForkTaskBuilder.java:66

• Deterministic default naming for branch(...) is new behavior (branch-<index> when name is null/blank) but there are no tests asserting this. Adding a small unit test in the func DSL test suite would help prevent regressions and verify the intended numbering/format, especially when mixing branch(...) and branches(...) calls.

  public <T, V> FuncForkTaskBuilder branch(
      String name, Function<T, V> function, Class<T> argParam) {
    if (name == null || name.isBlank()) {
      name = "branch-" + this.items.size();
    }
    this.items.add(
        new TaskItem(
            name,
            new Task().withCallTask(new CallTaskJava(CallJava.function(function, argParam)))));
    return this;

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[Copilot]

The auto-generated name uses this.list.size() from the current list builder instance. Since WorkflowBuilder.tasks(...) can be invoked multiple times and each call creates a new DoTaskBuilder / TaskItemListBuilder with an empty list, auto-naming will restart at *-0 on each invocation. That can produce duplicate task names in the final workflow, which will break downstream execution/visualization logic that keys by task name (e.g., maps keyed by item.getName()). Consider deriving the index from the merged workflow-level task list (or maintaining a workflow-scoped counter / offset) so names remain unique across multiple .tasks(...) appends.