wip(freestyle/acr): grounding & edit-tool fixes + ACR-compiler experiment

This branch's uncommitted WIP, committed together (entangled at file level).
Distinct pieces of work:

Freestyle QA fixes (this session):
- FileEditTool: pre-validate replace anchor in validateRequest — reject a
  missing/ambiguous target BEFORE the approval gate, mirroring read/write's
  file-not-found / read-before-write pre-checks. Shared not-found/ambiguous
  messages between validate and execute so they can't drift.
- PlanGrounder: add `scanned` flag; when no RepoMapComputedEvent was recorded,
  repoMapPaths is "unknown" not "empty workspace" — skip scope grounding
  (which proves a path ABSENT) so real paths (apps/server/**) aren't falsely
  rejected. Build-manifest check still runs.
- FreestyleDriver: wire scanned=(repoMap!=null); on plan rejection emit a
  session-terminal WorkflowFailedEvent so a rejected run reads FAILED, not the
  COMPLETED-lie (last verdict was the planning-phase WorkflowCompleted).
- ServerModule: resolve project-memory workspace root from the session's bound
  workspace (sessionWorkspaceRoot) instead of boot-static pm.repoRoot(), fixing
  the workspace-binding divergence (correx vs empty scratch dir). Retire tracked
  in Vikunja #266.
- LaunchRegistrationRaceTest: join registered jobs before asserting launchCount
  — computeIfAbsent returns the Job immediately but the fire-and-forget launch
  body lagged awaitAll (the 49-vs-50 flake).

ACR concept-compiler experiment (pre-existing WIP on this branch):
- ExecutionPlanCompiler/Model/PlanLinter, #264 needs-seam (sessionArtifacts),
  LSP diagnostics subsystem (LspDiagnosticEvents/Runner/Lsp4j), BootWorkspace,
  config surface, workflow prompts/schemas, orchestrator advance-don't-rerun.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

examples/workflows/freestyle_planning.toml

@@ -12,7 +12,7 @@ allowed_tools = ["file_read", "list_dir", "shell"]
 token_budget = 16384
 max_retries = 2
 
-# analyst writes no files, but it owns task framing: task_search/task_context (read-only) find
+# analyst writes no files, but it owns task framing and the fixed definition of done:
 # existing work; task_create (T2, approval-gated — a task is an event-log entry, not a file write)
 # opens a single task; task_decompose (T2, one approval for the whole graph) splits a goal with
 # dependency seams into parent + DEPENDS_ON-linked children. Either way the analysis names the task
@@ -20,7 +20,8 @@ max_retries = 2
 [[stages]]
 id = "analyst"
 prompt = "prompts/analyst_freestyle.md"
-produces = [{ name = "analysis", kind = "analysis" }]
+needs = ["discovery"]
+produces = [{ name = "dod", kind = "dod" }]
 allowed_tools = ["file_read", "list_dir", "shell", "task_search", "task_context", "task_create", "task_decompose"]
 token_budget = 16384
 max_retries = 2
@@ -30,7 +31,7 @@ id = "architect"
 requires_approval = true
 inject_artifact_kinds = true
 prompt = "prompts/architect_freestyle.md"
-needs = ["analysis"]
+needs = ["dod"]
 produces = [{ name = "execution_plan", kind = "execution_plan" }]
 token_budget = 16384
 max_retries = 2
@@ -47,7 +48,7 @@ id = "analyst-to-architect"
 from = "analyst"
 to = "architect"
 condition_type = "artifact_validated"
-condition_artifact_id = "analysis"
+condition_artifact_id = "dod"
 
 [[transitions]]
 id = "architect-to-done"