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/types/index.ts

@@ -68,3 +68,4 @@ export * from './plan.js';
 export * from './orchestrator.js';
 export * from './update.js';
 export * from './workflow-run.js';
+export * from './search.js';

src/types/search.ts

@@ -0,0 +1,77 @@
+/**
+ * @fileoverview Cross-session federated search types (COD-9).
+ *
+ * Defines the typed shapes for `GET /api/search` — a bounded, in-memory
+ * federated search across three v1 sources: live sessions/cases, run-summary
+ * timeline events, and per-session attachment file paths. Terminal-buffer scans
+ * and any persisted index are explicitly out of scope for v1.
+ *
+ * Key exports:
+ * - SearchSourceType — the federated source kinds, also the group order key.
+ * - SearchResult — a single typed result card (source, session id/name,
+ *   timestamp, snippet, jump-to action target).
+ * - SearchJumpTarget — where the frontend should navigate when a card is opened.
+ * - SearchResponseData — grouped result payload returned in the ApiResponse envelope.
+ *
+ * No I/O, no dependencies on other domain modules. The pure search core lives
+ * in `src/search-service.ts`; the route wrapper in `src/web/routes/search-routes.ts`.
+ */
+
+/** Federated source kinds. Group/render order is sessions → events → files. */
+export type SearchSourceType = 'session' | 'event' | 'file';
+
+/** Where the frontend should jump when a result card is activated. */
+export interface SearchJumpTarget {
+  /** Kind of navigation target. */
+  kind: 'session' | 'run-summary' | 'file-preview';
+  /** Owning Codeman session id (always present — every result is session-scoped). */
+  sessionId: string;
+  /**
+   * Secondary identifier for the target:
+   * - kind 'run-summary': the run-summary event id
+   * - kind 'file-preview': the attachment history item id
+   * - kind 'session': undefined (the sessionId is sufficient)
+   */
+  targetId?: string;
+  /**
+   * Workspace-relative path for file-preview targets. Never an absolute path —
+   * server-private external paths are intentionally omitted to avoid leakage.
+   */
+  relativePath?: string;
+}
+
+/** A single typed search result card. */
+export interface SearchResult {
+  /** Which federated source produced this result. */
+  type: SearchSourceType;
+  /** Owning Codeman session id. */
+  sessionId: string;
+  /** Display name of the owning session / case. */
+  sessionName: string;
+  /** Millisecond timestamp used for recency ranking and display. */
+  timestamp: number;
+  /** Short, already-truncated snippet describing the match. */
+  snippet: string;
+  /** True when the query matched the primary name/path exactly (case-insensitive). */
+  exactMatch: boolean;
+  /** Navigation target for the jump-to action. */
+  jumpTo: SearchJumpTarget;
+}
+
+/** A group of results for one source type, in render order. */
+export interface SearchResultGroup {
+  type: SearchSourceType;
+  results: SearchResult[];
+}
+
+/** Payload returned as `data` inside the standard ApiResponse envelope. */
+export interface SearchResponseData {
+  /** The normalized query that was executed. */
+  query: string;
+  /** Results grouped by source type, ordered sessions → events → files. */
+  groups: SearchResultGroup[];
+  /** Total number of results across all groups (after caps applied). */
+  totalResults: number;
+  /** True if any group or the total was capped (more matches existed). */
+  truncated: boolean;
+}