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/run.ts

@@ -254,13 +254,11 @@ function shouldRetry(result: AgentResult, validation: ValidationResult): RetryDe
   if (setOutputCheck && !setOutputCheck.passed) {
     // if the output contains rate limit indicators, use the longer backoff
     // (the agent process may have succeeded but the subagent hit quota limits)
-    const backoffMs = isRateLimited(result.output) ? RATE_LIMIT_BACKOFF_MS : FLAKY_RETRY_BACKOFF_MS;
+    const rateLimited = isRateLimited(result.output);
     return {
       retry: true,
-      reason: isRateLimited(result.output)
-        ? "rate limited (set_output cascade)"
-        : "set_output not called (cascade)",
-      backoffMs,
+      reason: rateLimited ? "rate limited (set_output cascade)" : "set_output not called (cascade)",
+      backoffMs: rateLimited ? RATE_LIMIT_BACKOFF_MS : FLAKY_RETRY_BACKOFF_MS,
     };
   }
 
@@ -312,9 +310,9 @@ async function runTestForAgent(ctx: RunContext): Promise<ValidationResult> {
     env.OPENCODE_MODEL ??= "anthropic/claude-sonnet-4-5";
   }
 
-  // gemini: use flash for all tests (including mini-effort) to avoid pro quota limits
+  // gemini: use 2.5 pro for testing
   if (ctx.agent === "gemini") {
-    env.GEMINI_MODEL ??= "gemini-3-flash-preview";
+    env.GEMINI_MODEL ??= "gemini-2.5-pro";
   }
 
   // build file-based env vars for MCP servers that don't inherit parent env