feat: paired review system overhaul — unified service, configurable agents, silent output removal

- Remove UNIFIED_MODE legacy: single service manages all 3 Discord bots
- Add OWNER_AGENT_TYPE / REVIEWER_AGENT_TYPE env vars for configurable agent selection
- Fix Discord channel routing: reviewer output goes through correct bot (discord/discord-review)
- Fix channel name assignment: explicit names prevent agentTypeFilter collision
- Remove silent output suppression system: harness-level protections replace prompt workarounds
- Add reviewer approval detection: DONE marker on first line stops ping-pong
- Include user's original message in reviewer prompt for context
- Fix round_trip_count auto-reset on new user message
- Fix session ID conflict: reviewer doesn't reuse owner's session
- Fix pending progress text flush in runner on close sentinel
- Promote buffered intermediate text to final result when result event has no text
- Remove legacy files: .env.codex.example, .env.codex-review.example, migrate-unify.cjs
- Update CLAUDE.md: server-side build deployment, unified architecture docs

src/config.ts

@@ -22,9 +22,6 @@ export const SERVICE_AGENT_TYPE: AgentType =
       ? 'codex'
       : 'claude-code';
 
-/** Unified mode: single process manages all bots. Disable with UNIFIED_MODE=0. */
-export const UNIFIED_MODE = getEnv('UNIFIED_MODE') !== '0';
-
 export function normalizeServiceId(serviceId: string): string {
   if (serviceId === 'codex') {
     return CODEX_MAIN_SERVICE_ID;
@@ -92,6 +89,25 @@ export const RECOVERY_CONCURRENT_AGENTS = parseInt(
 );
 
 // ── Paired review ─────────────────────────────────────────────────
+
+/** Owner agent type. Default: codex. Set OWNER_AGENT_TYPE=claude-code to use Claude as owner. */
+const rawOwnerAgentType = getEnv('OWNER_AGENT_TYPE');
+export const OWNER_AGENT_TYPE: AgentType =
+  rawOwnerAgentType === 'codex' || rawOwnerAgentType === 'claude-code'
+    ? rawOwnerAgentType
+    : 'codex';
+
+/** Reviewer agent type. Default: claude-code. Set REVIEWER_AGENT_TYPE=codex to use Codex as reviewer. */
+const rawReviewerAgentType = getEnv('REVIEWER_AGENT_TYPE');
+export const REVIEWER_AGENT_TYPE: AgentType =
+  rawReviewerAgentType === 'codex' || rawReviewerAgentType === 'claude-code'
+    ? rawReviewerAgentType
+    : 'claude-code';
+
+/** Service ID for the reviewer based on agent type. */
+export const REVIEWER_SERVICE_ID_FOR_TYPE =
+  REVIEWER_AGENT_TYPE === 'claude-code' ? CLAUDE_SERVICE_ID : CODEX_REVIEW_SERVICE_ID;
+
 // Max owner↔reviewer round trips per task. 0 = unlimited.
 const rawMaxRoundTrips = getEnv('PAIRED_MAX_ROUND_TRIPS') || '10';
 export const PAIRED_MAX_ROUND_TRIPS =