…n pattern

Adds a step-by-step migration recipe (attribute + context-parameter + drop the
AIT Test Context var), before/after example, rules (whole-codeunit, auto-detect),
variations (multi-turn, harms/adversarial, custom providers) and a checklist.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Migrating AIT evals to the language-first [TestDataSource] construct moves the
per-case fan-out to the platform test runner, so the toolkit's classic per-case
bracketing (Test Runner - Mgt.OnBefore/OnAfterTestMethodRun subscribers, which only
run under an AIT suite) no longer engages. This adds the platform-native seam:

- codeunit 149050 "AIT Test Handler" implements System.Testability.ITestHandler.
  OnBeforeTestCaseRun resets per-case accuracy/turns/token accounting and opens the
  run-procedure output scope; OnAfterTestCaseRun records the case outcome. Consuming
  eval codeunits opt in via TestHandlers = "AIT Test Handler".
- enumextension 149035 registers it under the platform TestHandler enum.
- "AIT DD Current Case" now buffers the per-case identity/outcome (in memory, so it
  survives the function isolation rollback) and flushes one AIT Log Entry from the
  out-of-isolation OnAfterTestMethodRun seam (decision C8-A). Note: that seam is
  raised by the Test Runner - Mgt runner (AL Test Tool / Test Suite Mgt); the pure
  platform test-execution path (al CLI) does not raise it, so log persistence there
  is a tracked follow-up.
- "AIT Test Suite Mgt.".AddDataDrivenLogEntry writes a per-case log entry with a
  session-scoped Run ID when there is no AIT suite; "AIT Test Run Iteration".
  IsRunningUnderAITSuite gates the handler off under an AIT suite to avoid double
  logging.
- Register the new objects in the toolkit object permission set and document the
  TestHandlers step in the migration guide.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

AddDataDrivenLogEntry now calls AgentTestContextImpl.LogAgentTasks after inserting
the AIT Log Entry, matching the classic AddLogEntry path so agent-eval task
correlation is preserved for language-first evals running on the platform runner.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

…tion)

Now that the platform runs ITestHandler hooks outside the per-function isolation
scope, the handler can write the AIT Log Entry directly in OnAfterTestCaseRun and it
persists past the case rollback. Remove the buffer/flush workaround: the pending-case
state and the OnAfterTestMethodRun flush subscriber in AIT DD Current Case, and
AIT DD Current Case is reduced to the dataset-lineage bridge + RunId + case-start
baseline.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

…only (D8)

Language-first detection is now solely CodeUnit Metadata.\"Has Test Data Source\" (platform field
12). Removes the interim \"Language First\" line flag (AIT Test Method Line field 8, its page control,
and the import/export XMLPort field-attribute) and the OR'd fallback in ExpandCodeunit. No backward
compatibility to preserve (unreleased).

Toolkit compiles cleanly against the reshaped symbols.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Addresses three single-instance state bugs that dropped or mis-attributed per-case logs when a
language-first eval runs on the platform test runner:
 - B2 (output lost): AddDataDrivenLogEntry read the per-case output from the handler's own
   (non-SingleInstance) "AIT Test Suite Mgt." instance, which is always empty. It now reads through
   the SingleInstance "AIT Test Context Impl." (new ConsumeRunProcedureOutput) - the same instance the
   test body wrote the output to.
 - B1 (stale lineage): the current case was bound lazily (only when the body first read its input), so
   a case that never touched its context logged the previous case's dataset lineage. GetTestCase now
   binds the current case eagerly at materialization (runs once per executing case, before the body and
   the OnAfterTestCaseRun log write).
 - B3 (leaked suite flag): AIT Test Run Iteration set ActiveAITTestSuite but never cleared it, so a
   standalone platform-runner data-driven run in the same session was mistaken for a suite run and the
   handler skipped its per-case logging. It is now cleared after each iteration.

Toolkit compiles cleanly against the reshaped symbols. NOTE: deferred (need the full toolkit app stack
to validate, or a design decision): the OnBeforeTestCaseRun scenario-start turn-count ordering, and the
language-first credit-limit skip re-hook (the limit provider is an AIT-suite concept; standalone
platform-runner runs have no suite).

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

…ta-driven evals

Re-hooks the credit-limit skip for language-first evals run on the platform test runner (no AIT
suite). AIT Test Handler.OnBeforeTestCaseRun now checks the global monthly Copilot-credit limit
(AIT Eval Monthly Copilot Cred., an environment/company budget - not suite-scoped) and, when
enforcement is enabled and the limit is reached, calls Context.Skip() (reported Skipped by the
platform runner) and writes a Skipped AIT Log Entry via the new LogSkippedDataDrivenEval (mirrors
AddDataDrivenLogEntry with Status::Skipped + reason, keyed by RunId/codeunit/procedure/case; the
existing LogSkippedEval is suite-only). Enforcement disabled (default) -> IsLimitReached is false
-> no-op. Mirrors the classic app-suite behavior in AIT Test Run Iteration.OnBeforeTestMethodRun.

Toolkit compiles cleanly against the reshaped symbols.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>