merge: integrate feat/backlog-burndown into master

master had advanced 16 commits past feat/backlog-burndown's base, and the two
branches independently built four of the same features. Resolved 26 conflicts.

Overlap features — kept master's implementation (more complete / production-wired /
more robust), dropped the feature branch's parallel constellation:
- llama-server health probe: kept master's event-store-backed tps probe; dropped the
  branch's LlamaLivenessClient (liveness-only, throughput unwired).
- event-store probe: kept master's EventStoreHealthProbe; dropped EventStoreLatencyProbe.
- brief echo-back gate: kept master's BriefEchoDiff (Jaccard, tolerates rewording);
  dropped the branch's exact-set-diff BriefEchoComparator/Extractor.
- static-first reviewer: kept master's command/exit-code gate (ProcessStaticAnalysisRunner,
  wired); dropped the branch's structured-finding static_check stage (no-op seam).
  Its structured-findings model is filed as a follow-up in BACKLOG.

Feature-branch net-new work brought in and kept (master had none):
- native task tracking (aggregate, agent tools wired into analyst/implementer/reviewer,
  dependency graph + gates, decompose, REST/CLI, TUI task board)
- critique-outcome producer (role-rel §6 — master had deferred it)
- stage-level plan checkpointing (C-A2, folded into runPostStageGates)
- CLAUDE.md/AGENTS.md L0 standing context
- cross-session grants + TUI (grant scopes/revoke, @ picker, session resume browser)

Verified: full Gradle compile (all modules + tests) green; tests pass for core:events,
core:kernel, infrastructure:workflow, apps:server, apps:cli, testing:integration; tui-go
go build + go test green.

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

examples/workflows/role_pipeline.toml

@@ -33,7 +33,7 @@ start = "analyst"
 id = "analyst"
 prompt = "prompts/analyst.md"
 produces = [{ name = "analysis", kind = "analysis" }]
-allowed_tools = ["file_read", "ShellTool"]
+allowed_tools = ["file_read", "ShellTool", "task_search", "task_context", "task_create"]
 ground_references = true
 token_budget = 16384
 max_retries = 2
@@ -87,7 +87,10 @@ id = "implementer"
 prompt = "prompts/implementer.md"
 needs = ["impl_plan"]
 produces = [{ name = "patch", kind = "file_written" }]
-allowed_tools = ["file_read", "file_write", "file_edit", "ShellTool"]
+allowed_tools = [
+    "file_read", "file_write", "file_edit", "ShellTool",
+    "task_create", "task_update", "task_context", "task_search",
+]
 # static_analysis = ["./gradlew compileKotlin -q", "./gradlew detekt -q"]
 token_budget = 32768
 max_retries = 3
@@ -100,6 +103,7 @@ id = "reviewer"
 prompt = "prompts/reviewer.md"
 needs = ["patch", "impl_plan", "analysis"]
 produces = [{ name = "review_report", kind = "review_report" }]
+allowed_tools = ["task_context", "task_update"]
 token_budget = 32768
 max_retries = 2