refactor delegation system, add PR summary comments, and improve code quality (#334)

* refactor delegation system and add PR summary comments

Delegation system:
- replace mode-based delegation with select_mode → delegate two-step flow
- orchestrator crafts self-contained subagent prompts (clean context — no system/repo/event instructions leak)
- add role-based tool filtering via FastMCP authenticate hook (?role=subagent hides orchestrator-only tools)
- add select_mode tool for orchestrator guidance per mode
- add ask_question tool for lightweight research subagents
- extract shared subagent lifecycle into subagent.ts (create, complete, stdout, instructions)
- route set_output to per-subagent state when activeSubagentId is set
- track per-subagent state (SubagentState Map) replacing boolean delegationActive flag
- capture and aggregate AgentUsage across all agents (claude, codex, gemini, opencode)
- write usage summary table to GitHub job summary
- block built-in subagent spawning (Task for Claude, Task(*) for Cursor)
- increase activity timeout from 60s to 300s (subagent thinking phases)
- fix gh CLI misguidance in system prompt — explicitly forbid usage

PR summary comments:
- add prSummaryComment trigger (DB schema + migrations + Zod + UI toggle)
- dispatch mini-effort summary job alongside PR review on pr.created
- add update_pull_request_body MCP tool
- add defaultEffort option to webhook dispatch

Hardening:
- rewrite delegate/selectMode tests with simulated state management
- add toolFiltering.test.ts for role extraction, canAccess, set_output routing
- remove non-null assertions for PULLFROG_TEMP_DIR (proper error throws)
- use fetchWithRetry for direct tarball downloads
- DRY fix for rate limit check in test runner

Co-authored-by: Cursor <cursoragent@cursor.com>

* fix: add type keyword to Effort import in handleWebhook.ts

Co-authored-by: Cursor <cursoragent@cursor.com>

* clean up delegation system, improve code quality across the codebase

- simplify delegate tool to instructions + effort params with subagent lifecycle in subagent.ts
- add select_mode and ask_question orchestrator-only tools with canAccess filtering
- replace delegate.test.ts/selectMode.test.ts with toolFiltering.test.ts (live MCP integration)
- add set_output routing for subagent context and AgentUsage tracking across all agents
- add PR summary comment trigger (schema, UI, webhook dispatch with silent flag)
- add update_pull_request_body MCP tool
- fix changed-agents.sh to always include claude canary for non-agent action changes
- fix cursor pagination bug in getSelectedInstallationReposPage
- remove destructuring patterns, inline type definitions, and unsafe type casts
- replace non-null assertions with explicit checks in install.ts
- convert multi-param functions to single param objects (postCleanup, runActionLocal, etc.)
- use isHttpError helper in API routes instead of catch-any patterns
- add adhoc test fixtures for delegation scenarios (context isolation, error handling, synthesis, etc.)

Co-authored-by: Cursor <cursoragent@cursor.com>

* no subagent mutation, one mcp per subagent

* address review feedback: parallel-safe usage tracking, subagent isolation, minor improvements

* fix subagent state isolation: replace Object.freeze with shallow copy

Object.freeze throws TypeErrors when subagent tools (checkout_pr,
report_progress) write scalar properties to toolState. A shallow copy
achieves the same isolation for scalar fields while allowing tools to
work normally. Shared references (subagents Map, usageEntries array)
remain shared for coordination.

---------

Co-authored-by: Cursor <cursoragent@cursor.com>
Co-authored-by: pullfrog[bot] <226033991+pullfrog[bot]@users.noreply.github.com>

test/adhoc/delegateTimeout.ts

@@ -12,8 +12,8 @@ import { defineFixture, getAgentOutput, getStructuredOutput } from "../utils.ts"
 
 const fixture = defineFixture(
   {
-    prompt: `Delegate to the Plan mode with auto effort. Pass these instructions to the subagent:
-"Carefully analyze the following engineering question and provide a thorough response, then call set_output with the value 'DELEGATE_TIMEOUT_PASSED'.
+    prompt: `Select the Plan mode via select_mode, then delegate with auto effort. Your subagent instructions should be:
+"Carefully analyze the following engineering question. Think through each point thoroughly before finishing.
 
 Question: Design a comprehensive error handling strategy for a distributed microservices architecture. Consider:
 1. Circuit breaker patterns — when to open, half-open, close. What thresholds to use.
@@ -22,7 +22,9 @@ Question: Design a comprehensive error handling strategy for a distributed micro
 4. Health check endpoints — liveness vs readiness probes, dependency health checks.
 5. Graceful degradation — fallback responses, feature flags, bulkhead pattern.
 
-Provide a detailed analysis covering ALL 5 points with concrete examples before calling set_output."`,
+After you have finished your analysis, call gh_pullfrog/set_output with EXACTLY the string 'DELEGATE_TIMEOUT_PASSED' — not your analysis, just that exact string."
+
+After the delegation completes, call set_output yourself with the subagent's result (forward it verbatim).`,
     effort: "auto",
     timeout: "8m",
   },
@@ -35,8 +37,7 @@ function validator(result: AgentResult): ValidationCheck[] {
 
   const setOutputCalled = output !== null;
   const correctValue = setOutputCalled && /DELEGATE_TIMEOUT_PASSED/i.test(output);
-  const delegationOccurred = /» delegating to \w+ mode/i.test(agentOutput);
-  // the critical check: no activity timeout occurred
+  const delegationOccurred = /» delegating subagent=/i.test(agentOutput);
   const noActivityTimeout = !/activity timeout/i.test(agentOutput);
 
   return [