COD-9 add cross-session search backend (GET /api/search) v1

Bounded federated search over in-memory stores (sessions/cases, run-summary
events, file paths). Zod-validated query (q 1-200 chars, types csv, limit 1-60),
grouped session->event->file with exact-match-first + recency tiebreak, total
cap 60 + per-group cap 25, snippet cap 200, path-safety (relativePath only).
Frontend search box (history panel) deferred to next cycle; resume/history-prompt
text matching deferred to v1.1 (lives in large on-disk files, out of v1 bounded scope).

New: src/search-service.ts (pure core), src/types/search.ts, src/web/routes/search-routes.ts.
Tests: test/search-service.test.ts (14), test/routes/search-routes.test.ts (10).

src/web/routes/index.ts

@@ -17,4 +17,5 @@ export { registerRalphRoutes } from './ralph-routes.js';
 export { registerPlanRoutes } from './plan-routes.js';
 export { registerOrchestratorRoutes } from './orchestrator-routes.js';
 export { registerClipboardRoutes } from './clipboard-routes.js';
+export { registerSearchRoutes } from './search-routes.js';
 export { registerWsRoutes } from './ws-routes.js';

src/web/routes/search-routes.ts

@@ -0,0 +1,162 @@
+/**
+ * @fileoverview Cross-session federated search route (COD-9).
+ *
+ * Registers `GET /api/search?q=&types=&limit=` — a bounded, in-memory search
+ * across three v1 sources, returned in the standard ApiResponse envelope:
+ *   1. sessions/cases — name, working directory, session id
+ *   2. run-summary events — event title/details (from the live run-summary trackers)
+ *   3. file paths — per-session attachment history (workspace-relative paths only)
+ *
+ * This route is a THIN wrapper: it harvests the source arrays from the live
+ * server stores (held on the route context) in a bounded way, then delegates
+ * grouping/ranking/capping to the pure `searchSources()` core in
+ * `src/search-service.ts`. Terminal-buffer scanning and any persisted index are
+ * out of scope for v1.
+ *
+ * Safety: query input is Zod-validated (length-bounded `q`, allowlisted `types`,
+ * numeric `limit`); only workspace-relative file paths are ever exposed (the
+ * server-private `externalPath` on attachment history is never read here); and
+ * the pure core enforces a per-group and total result cap so a broad query
+ * cannot return an unbounded payload. No terminal output is read.
+ *
+ * Endpoints: GET /api/search
+ */
+
+import { FastifyInstance } from 'fastify';
+import { parseBody } from '../route-helpers.js';
+import { SearchQuerySchema } from '../schemas.js';
+import {
+  searchSources,
+  type SearchSources,
+  type SessionSearchInput,
+  type EventSearchInput,
+  type FileSearchInput,
+} from '../../search-service.js';
+import type { SearchSourceType } from '../../types/search.js';
+import type { SessionPort, InfraPort } from '../ports/index.js';
+
+/**
+ * Per-source harvest caps. These bound how much in-memory data we hand to the
+ * pure core BEFORE it applies its own result caps — they keep the harvest itself
+ * cheap on large deployments (e.g. 50 sessions × many events). They are
+ * deliberately well above the result caps so ranking still sees enough candidates.
+ */
+const MAX_EVENTS_PER_SESSION = 500;
+
+interface SessionLike {
+  id: string;
+  name: string;
+  workingDir: string;
+  lastActivityAt?: number;
+  createdAt?: number;
+  attachmentHistory?: Array<{
+    id: string;
+    fileName: string;
+    relativePath?: string;
+    timestamp?: number;
+    mtimeMs?: number;
+  }>;
+}
+
+/**
+ * Harvest the three source arrays from the live in-memory stores. Reads only
+ * bounded, already-loaded data — no disk I/O, no terminal buffers.
+ */
+function harvestSources(ctx: SessionPort & InfraPort): SearchSources {
+  const sessions: SessionSearchInput[] = [];
+  const events: EventSearchInput[] = [];
+  const files: FileSearchInput[] = [];
+
+  for (const raw of ctx.sessions.values()) {
+    const s = raw as unknown as SessionLike;
+    const sessionName = s.name ?? '';
+    const timestamp = s.lastActivityAt ?? s.createdAt ?? 0;
+
+    sessions.push({
+      sessionId: s.id,
+      sessionName,
+      workingDir: s.workingDir ?? '',
+      timestamp,
+    });
+
+    // Files: per-session attachment history. Only the workspace-relative path is
+    // surfaced; the server-private externalPath is intentionally never read.
+    const history = s.attachmentHistory ?? [];
+    for (const item of history) {
+      files.push({
+        sessionId: s.id,
+        sessionName,
+        fileName: item.fileName,
+        relativePath: item.relativePath,
+        timestamp: item.timestamp ?? item.mtimeMs ?? timestamp,
+        itemId: item.id,
+      });
+    }
+  }
+
+  // Events: from the live run-summary trackers, keyed by session id.
+  for (const [sessionId, tracker] of ctx.runSummaryTrackers) {
+    const session = ctx.sessions.get(sessionId) as unknown as SessionLike | undefined;
+    const sessionName = session?.name ?? '';
+    const summary = tracker.getSummary();
+    // Newest events are most relevant; cap the per-session harvest.
+    const evts = summary.events.slice(-MAX_EVENTS_PER_SESSION);
+    for (const e of evts) {
+      events.push({
+        sessionId,
+        sessionName,
+        eventId: e.id,
+        title: e.title,
+        details: e.details ?? '',
+        timestamp: e.timestamp,
+      });
+    }
+  }
+
+  return { sessions, events, files };
+}
+
+export function registerSearchRoutes(app: FastifyInstance, ctx: SessionPort & InfraPort): void {
+  app.get('/api/search', async (req) => {
+    // Zod-validate the query. parseBody throws a structured 400 on failure.
+    const { q, types, limit } = parseBody(SearchQuerySchema, req.query);
+
+    const allowed: Set<SearchSourceType> | null = types
+      ? new Set(
+          types
+            .split(',')
+            .map((t) => t.trim())
+            .filter(Boolean) as SearchSourceType[]
+        )
+      : null;
+
+    const sources = harvestSources(ctx);
+
+    // Apply the optional source-type filter before searching so excluded
+    // sources never contribute to (or consume budget in) the result set.
+    const filtered: SearchSources = {
+      sessions: !allowed || allowed.has('session') ? sources.sessions : [],
+      events: !allowed || allowed.has('event') ? sources.events : [],
+      files: !allowed || allowed.has('file') ? sources.files : [],
+    };
+
+    const result = searchSources(q, filtered);
+
+    // Optional caller-supplied total cap (always on top of the core's hard caps).
+    if (limit !== undefined && result.totalResults > limit) {
+      let remaining = limit;
+      const cappedGroups = [];
+      for (const group of result.groups) {
+        if (remaining <= 0) break;
+        const slice = group.results.slice(0, remaining);
+        remaining -= slice.length;
+        cappedGroups.push({ type: group.type, results: slice });
+      }
+      result.groups = cappedGroups;
+      result.totalResults = limit;
+      result.truncated = true;
+    }
+
+    return { success: true, data: result };
+  });
+}