refactor: consolidate ~70 scattered constants into 6 new config files (phase 6)

Create 6 domain-focused config files in src/config/ to centralize operational
tuning knobs that were scattered across 15+ source files:

- server-timing.ts: SSE batching, state debounce, scheduled runs, error recovery
- auth-config.ts: session TTL, rate limits, hook timeout
- tunnel-config.ts: QR token rotation, tunnel process lifecycle
- terminal-limits.ts: input length, terminal cols/rows, session name
- ai-defaults.ts: AI model string, idle/plan context limits
- team-config.ts: poll interval, cache sizes

Eliminates all cross-file duplicates:
- AI model string: 5 occurrences → 1 (config only)
- STATS_COLLECTION_INTERVAL_MS: 2 → 1
- timeout: 10000 in hooks-config: 6 → 0 (now HOOK_TIMEOUT_MS)
- MAX_TRACKED_AGENTS shadow: removed, imports from map-limits

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/web/routes/mux-routes.ts

@@ -5,9 +5,7 @@
 
 import { FastifyInstance } from 'fastify';
 import type { InfraPort } from '../ports/index.js';
-
-// Stats collection interval (2 seconds) — matches server.ts constant
-const STATS_COLLECTION_INTERVAL_MS = 2000;
+import { STATS_COLLECTION_INTERVAL_MS } from '../../config/server-timing.js';
 
 export function registerMuxRoutes(app: FastifyInstance, ctx: InfraPort): void {
   app.get('/api/mux-sessions', async () => {

src/web/routes/respawn-routes.ts

@@ -10,6 +10,7 @@ import { RespawnConfigSchema, InteractiveRespawnSchema, RespawnEnableSchema } fr
 import { findSessionOrFail, autoConfigureRalph } from '../route-helpers.js';
 import type { SessionPort, EventPort, RespawnPort, ConfigPort, InfraPort } from '../ports/index.js';
 import { getLifecycleLog } from '../../session-lifecycle-log.js';
+import { AI_CHECK_MODEL, AI_IDLE_CHECK_MAX_CONTEXT, AI_PLAN_CHECK_MAX_CONTEXT } from '../../config/ai-defaults.js';
 
 /** No-op EventPort used to suppress broadcasts during pre-start ralph configuration. */
 const noopEventPort: EventPort = {
@@ -170,13 +171,15 @@ export function registerRespawnRoutes(
       autoAcceptPrompts: config.autoAcceptPrompts ?? currentConfig?.autoAcceptPrompts ?? true,
       autoAcceptDelayMs: config.autoAcceptDelayMs ?? currentConfig?.autoAcceptDelayMs ?? 8000,
       aiIdleCheckEnabled: config.aiIdleCheckEnabled ?? currentConfig?.aiIdleCheckEnabled ?? true,
-      aiIdleCheckModel: config.aiIdleCheckModel ?? currentConfig?.aiIdleCheckModel ?? 'claude-opus-4-5-20251101',
-      aiIdleCheckMaxContext: config.aiIdleCheckMaxContext ?? currentConfig?.aiIdleCheckMaxContext ?? 16000,
+      aiIdleCheckModel: config.aiIdleCheckModel ?? currentConfig?.aiIdleCheckModel ?? AI_CHECK_MODEL,
+      aiIdleCheckMaxContext:
+        config.aiIdleCheckMaxContext ?? currentConfig?.aiIdleCheckMaxContext ?? AI_IDLE_CHECK_MAX_CONTEXT,
       aiIdleCheckTimeoutMs: config.aiIdleCheckTimeoutMs ?? currentConfig?.aiIdleCheckTimeoutMs ?? 90000,
       aiIdleCheckCooldownMs: config.aiIdleCheckCooldownMs ?? currentConfig?.aiIdleCheckCooldownMs ?? 180000,
       aiPlanCheckEnabled: config.aiPlanCheckEnabled ?? currentConfig?.aiPlanCheckEnabled ?? true,
-      aiPlanCheckModel: config.aiPlanCheckModel ?? currentConfig?.aiPlanCheckModel ?? 'claude-opus-4-5-20251101',
-      aiPlanCheckMaxContext: config.aiPlanCheckMaxContext ?? currentConfig?.aiPlanCheckMaxContext ?? 8000,
+      aiPlanCheckModel: config.aiPlanCheckModel ?? currentConfig?.aiPlanCheckModel ?? AI_CHECK_MODEL,
+      aiPlanCheckMaxContext:
+        config.aiPlanCheckMaxContext ?? currentConfig?.aiPlanCheckMaxContext ?? AI_PLAN_CHECK_MAX_CONTEXT,
       aiPlanCheckTimeoutMs: config.aiPlanCheckTimeoutMs ?? currentConfig?.aiPlanCheckTimeoutMs ?? 60000,
       aiPlanCheckCooldownMs: config.aiPlanCheckCooldownMs ?? currentConfig?.aiPlanCheckCooldownMs ?? 30000,
       durationMinutes: currentConfig?.durationMinutes,

src/web/routes/session-routes.ts

@@ -41,11 +41,12 @@ import type { SessionPort, EventPort, ConfigPort, InfraPort, AuthPort } from '..
 import { MAX_CONCURRENT_SESSIONS } from '../../config/map-limits.js';
 import { RunSummaryTracker } from '../../run-summary.js';
 
-// Constants
-const MAX_INPUT_LENGTH = 64 * 1024;
-const MAX_TERMINAL_COLS = 500;
-const MAX_TERMINAL_ROWS = 200;
-const MAX_SESSION_NAME_LENGTH = 128;
+import {
+  MAX_INPUT_LENGTH,
+  MAX_TERMINAL_COLS,
+  MAX_TERMINAL_ROWS,
+  MAX_SESSION_NAME_LENGTH,
+} from '../../config/terminal-limits.js';
 
 // Pre-compiled regex for terminal buffer cleaning (avoids per-request compilation)
 // eslint-disable-next-line no-control-regex