feat(FN-3803): add universal web fetch to reviewer, merger, and triage agen

The merge introduces the universal web fetch tool across reviewer/merger/triage agents (FN-3803, 4 commits) with docs and regression test, extracts the roadmap as a plugin scaffold in `plugins/fusion-plugin-reports` (FN-3166, FN-3165) while removing dashboard roadmap backend and associated tests, ad

Fusion-Task-Id: FN-3803

packages/cli/skill/fusion/references/engine-tools.md

@@ -18,7 +18,7 @@ These tools are **not** part of the user-invokable extension surface. They are i
 | `fn_memory_search` | triage, executor, heartbeat | Search project memory plus per-agent layered memory snippets | `query` (string), `limit?` (number) |
 | `fn_memory_get` | triage, executor, heartbeat | Read a bounded memory file window (including bounded per-agent layered paths) | `path` (string), `startLine?` (number), `lineCount?` (number) |
 | `fn_memory_append` | executor, heartbeat (when writable backend enabled) | Append memory notes with explicit scope: `scope="agent"` for private operating context, `scope="project"` for workspace-wide durable knowledge | `scope?` (`project` \| `agent`), `layer` (`long-term` \| `daily`), `content` (string) |
-| `fn_web_fetch` | executor, step-session, heartbeat | Lightweight HTTP fetch with HTML→text extraction, timeout/size caps, and SSRF guard (no JS rendering) | `url` (string), `prompt?` (string), `timeoutMs?` (number), `maxBytes?` (number) |
+| `fn_web_fetch` | executor, step-session, reviewer, merger, triage, heartbeat | Lightweight HTTP fetch with HTML→text extraction, timeout/size caps, and SSRF guard (no JS rendering) | `url` (string), `prompt?` (string), `timeoutMs?` (number), `maxBytes?` (number) |
 | `fn_research_run` | triage, executor | Start a bounded research run (optionally wait for completion) and return structured findings metadata | `query` (string), `wait_for_completion?` (boolean), `max_wait_ms?` (number) |
 | `fn_research_list` | triage, executor | List recent research runs with status/summary metadata | `status?` (`pending` \| `running` \| `completed` \| `failed` \| `cancelled`), `limit?` (number) |
 | `fn_research_get` | triage, executor | Read one research run's structured findings/citations payload | `id` (string) |

packages/engine/src/__tests__/reviewer.test.ts

@@ -201,7 +201,7 @@ describe("reviewStep — spec review type", () => {
     const opts = mockedCreateFnAgent.mock.calls[0][0];
     expect(opts.systemPrompt).toContain("## Project Memory");
     expect(opts.systemPrompt).toContain("Do not update memory during review");
-    expect(opts.customTools?.map((tool: any) => tool.name)).toEqual(["fn_memory_search", "fn_memory_get"]);
+    expect(opts.customTools?.map((tool: any) => tool.name)).toEqual(["fn_web_fetch", "fn_memory_search", "fn_memory_get"]);
   });
 
   it("omits reviewer memory tools and instructions when memory is disabled", async () => {
@@ -217,7 +217,7 @@ describe("reviewStep — spec review type", () => {
 
     const opts = mockedCreateFnAgent.mock.calls[0][0];
     expect(opts.systemPrompt).not.toContain("## Project Memory");
-    expect(opts.customTools).toBeUndefined();
+    expect(opts.customTools?.map((tool: any) => tool.name)).toEqual(["fn_web_fetch"]);
   });
 
   it("builds review request with spec-specific instructions", async () => {

packages/engine/src/__tests__/web-fetch-universal.test.ts

@@ -0,0 +1,36 @@
+import { readFileSync } from "node:fs";
+import { join } from "node:path";
+import { describe, expect, it } from "vitest";
+
+function readSource(file: string): string {
+  return readFileSync(join(import.meta.dirname, "..", file), "utf8");
+}
+
+describe("fn_web_fetch universal registration", () => {
+  it("executor registers fn_web_fetch", () => {
+    expect(readSource("executor.ts")).toContain("createWebFetchTool()");
+  });
+
+  it("step-session executor registers fn_web_fetch", () => {
+    expect(readSource("step-session-executor.ts")).toContain("createWebFetchTool()");
+  });
+
+  it("reviewer registers fn_web_fetch", () => {
+    expect(readSource("reviewer.ts")).toContain("customTools: [createWebFetchTool()");
+  });
+
+  it("merger registers fn_web_fetch", () => {
+    expect(readSource("merger.ts")).toContain("customTools: [reportBuildFailureTool, createWebFetchTool()]");
+  });
+
+  it("triage registers fn_web_fetch", () => {
+    expect(readSource("triage.ts")).toContain("createWebFetchTool(),");
+  });
+
+  it("heartbeat registers fn_web_fetch for task and no-task branches", () => {
+    const source = readSource("agent-heartbeat.ts");
+    expect(source).toContain("heartbeatTools.push(createWebFetchTool())");
+    expect(source).toContain("if (taskId)");
+    expect(source).toContain("else {");
+  });
+});

packages/engine/src/merger.ts

@@ -66,6 +66,7 @@ import { resolveAgentInstructions, buildSystemPromptWithInstructions } from "./a
 import type { ToolDefinition } from "@mariozechner/pi-coding-agent";
 import { Type } from "typebox";
 import { createRunAuditor, generateSyntheticRunId, type EngineRunContext } from "./run-audit.js";
+import { createWebFetchTool } from "./agent-tools.js";
 
 /** Conflict type classification for merge conflict resolution */
 export type ConflictType =
@@ -6443,7 +6444,7 @@ async function runAiAgentForCommit(params: AiAgentParams): Promise<{ success: bo
     cwd: rootDir,
     systemPrompt: mergerSystemPrompt,
     tools: "coding",
-    customTools: [reportBuildFailureTool],
+    customTools: [reportBuildFailureTool, createWebFetchTool()],
     onText: agentLogger.onText,
     onThinking: agentLogger.onThinking,
     onToolStart: agentLogger.onToolStart,

packages/engine/src/reviewer.ts

@@ -22,7 +22,7 @@ import {
   buildPluginPromptSection,
 } from "./agent-instructions.js";
 import { createFallbackModelObserver } from "./fallback-model-observer.js";
-import { createMemoryGetTool, createMemorySearchTool } from "./agent-tools.js";
+import { createMemoryGetTool, createMemorySearchTool, createWebFetchTool } from "./agent-tools.js";
 
 export const REVIEWER_SYSTEM_PROMPT = `You are an independent code and plan reviewer.
 
@@ -496,7 +496,7 @@ export async function reviewStep(
       cwd,
       systemPrompt: reviewerSystemPromptFinal,
       tools: "readonly",
-      customTools: memoryTools,
+      customTools: [createWebFetchTool(), ...(memoryTools ?? [])],
       onText: agentLogger ? agentLogger.onText : (delta) => options.onText?.(delta),
       onThinking: agentLogger?.onThinking,
       onToolStart: agentLogger?.onToolStart,

packages/engine/src/triage.ts

@@ -52,6 +52,7 @@ import {
   createListAgentsTool,
   createMemoryTools,
   createResearchTools,
+  createWebFetchTool,
   createTaskDocumentReadTool,
   createTaskDocumentWriteTool,
 } from "./agent-tools.js";
@@ -966,6 +967,7 @@ export class TriageProcessor {
               },
             }
             : undefined),
+          createWebFetchTool(),
           // Agent delegation tools — discover and delegate work to other agents.
           ...(this.options.agentStore ? [
             createListAgentsTool(this.options.agentStore),