feat: Wave 1 complete — state machine, Paseo hub, collision detection, PTY search

- Task state machine: TIMED_OUT state, retriable steps, timeout detection
- Paseo hub: paseo-client.ts (HTTP+CLI), PaseoBackend (AgentBackend), 14 tests
- Collision detection: collision-detector.ts, conflict-index.ts, ws-frames type
- PTY search: ring buffer, search route, capture-pane fallback

apps/booterm/src/routes/search.ts

@@ -0,0 +1,167 @@
+import type { FastifyInstance } from 'fastify';
+import { z } from 'zod';
+import { sanitizeId, tmuxSessionName, capturePane } from '../pty/manager.js';
+import { searchRingBuffer, clearBuffer } from '../pty/registry.js';
+
+const ParamsSchema = z.object({
+  sid: z.string(),
+  pid: z.string(),
+});
+
+const MAX_PATTERN_LENGTH = 200;
+
+// Zod-refined string: reject empty and overly-long patterns to prevent ReDoS
+const PatternQuerySchema = z
+  .string()
+  .min(1, 'pattern is required')
+  .max(MAX_PATTERN_LENGTH, `pattern must not exceed ${MAX_PATTERN_LENGTH} characters`);
+
+const QuerySchema = z.object({
+  pattern: PatternQuerySchema,
+  limit: z.coerce.number().int().min(1).max(500).default(50),
+  context: z.coerce.number().int().min(0).max(50).default(0),
+});
+
+interface SearchMatch {
+  line: number;
+  content: string;
+  contextBefore: string[];
+  contextAfter: string[];
+}
+
+interface SearchResponse {
+  matches: SearchMatch[];
+  total: number;
+  truncated: boolean;
+  source: 'ring' | 'capture';
+}
+
+/**
+ * Search a captured pane buffer using a regex. This is the fallback path
+ * when the ring buffer doesn't have enough matches.
+ */
+function grepBuffer(
+  text: string,
+  pattern: string,
+  limit: number,
+  context: number,
+): SearchMatch[] {
+  let re: RegExp;
+  try {
+    re = new RegExp(pattern, 'u');
+  } catch {
+    return [];
+  }
+
+  const lines = text.split('\n');
+  const results: SearchMatch[] = [];
+
+  for (let i = 0; i < lines.length; i++) {
+    if (results.length >= limit) break;
+    if (re.test(lines[i]!)) {
+      const contextBefore: string[] = [];
+      const contextAfter: string[] = [];
+      for (let c = 1; c <= context; c++) {
+        const ci = i - c;
+        if (ci >= 0) contextBefore.unshift(lines[ci]!);
+      }
+      for (let c = 1; c <= context; c++) {
+        const ci = i + c;
+        if (ci < lines.length) contextAfter.push(lines[ci]!);
+      }
+      results.push({
+        line: i + 1,
+        content: lines[i]!,
+        contextBefore,
+        contextAfter,
+      });
+    }
+  }
+
+  return results;
+}
+
+export function registerSearchRoutes(app: FastifyInstance, tmuxConfPath: string): void {
+  app.get<{
+    Params: { sid: string; pid: string };
+    Querystring: { pattern?: string; limit?: string; context?: string };
+  }>(
+    '/api/term/sessions/:sid/panes/:pid/search',
+    async (req, reply) => {
+      const p = ParamsSchema.safeParse(req.params);
+      if (!p.success) return reply.code(400).send({ error: 'bad_params' });
+
+      const sid = sanitizeId(p.data.sid);
+      const pid = sanitizeId(p.data.pid);
+      if (!sid || !pid) return reply.code(400).send({ error: 'bad_id_format' });
+
+      const q = QuerySchema.safeParse(req.query);
+      if (!q.success) {
+        return reply.code(400).send({
+          error: 'bad_query',
+          details: q.error.flatten().fieldErrors,
+        });
+      }
+
+      const { pattern, limit, context } = q.data;
+
+      // ── Path 1: ring buffer search (fast, no tmux interaction) ──
+      const ringMatches = searchRingBuffer(pid, pattern, { limit, context });
+      if (ringMatches.length >= limit) {
+        return reply.code(200).send({
+          matches: ringMatches,
+          total: ringMatches.length,
+          truncated: ringMatches.length >= limit,
+          source: 'ring' as const,
+        });
+      }
+
+      // ── Path 2: capture-pane + grep fallback (10s timeout) ──
+      const sessionName = tmuxSessionName(pid);
+
+      let capture: string;
+      try {
+        capture = await withTimeout(
+          capturePane(tmuxConfPath, sessionName, 5000),
+          10_000,
+        );
+      } catch (err) {
+        req.log.warn({ err, pid }, 'capture-pane timed out or failed');
+        return reply.code(200).send({
+          matches: ringMatches,
+          total: ringMatches.length,
+          truncated: false,
+          source: 'ring' as const,
+        });
+      }
+
+      if (!capture) {
+        // tmux pane may no longer exist — return whatever ring had
+        return reply.code(200).send({
+          matches: ringMatches,
+          total: ringMatches.length,
+          truncated: false,
+          source: 'ring' as const,
+        });
+      }
+
+      const captureMatches = grepBuffer(capture, pattern, limit, context);
+
+      return reply.code(200).send({
+        matches: captureMatches,
+        total: captureMatches.length,
+        truncated: captureMatches.length >= limit,
+        source: 'capture' as const,
+      });
+    },
+  );
+}
+
+function withTimeout<T>(promise: Promise<T>, ms: number): Promise<T> {
+  return Promise.race([
+    promise,
+    new Promise<never>((_, reject) =>
+      setTimeout(() => reject(new Error('timeout')), ms),
+    ),
+  ]);
+}