feat(channels): add human-like chat behavior

Squash merge PR #99 after resolving conflicts with current dev. PR CI run 26703381807 passed release-versioning, go, and web.

docs/05-channels-messaging.md

@@ -71,6 +71,16 @@ The consumer routes system messages based on sender ID prefixes:
 
 Normal channel messages pass through the shared inbound debouncer before agent execution. `gateway.inbound_debounce_ms` merges rapid text messages from the same `channel:chatID:senderID:agentID`; `0` means no debounce and positive values set the wait window. Agents can override the global value with `other_config.inbound_debounce_ms`; unset inherits the global config. Command/control messages such as `/stop`, `/reset`, and system escalations bypass the debouncer.
 
+### Human-like Delivery
+
+`gateway.chat_behavior` controls optional channel-only delivery polish:
+
+- `quick_ack` sends one short acknowledgement after a configurable delay, only for non-streaming channel runs.
+- `final_split` splits long final text replies into a bounded number of paragraph messages.
+- Per-channel `chat_behavior` overrides inherit the gateway config unless a field is explicitly set.
+
+Splitting is intentionally conservative. Replies containing fenced code, tables, lists, quotes, JSON/XML-ish blocks, or URL-only paragraphs remain a single message. Media replies and streaming deliveries are not split.
+
 **Multi-attachment coalescing (#63).** Messages carrying attachments do NOT bypass the debouncer — that pre-fix shortcut was the source of N-replies for one user action. Instead, when media is present the effective window is `max(configured, mediaFloor)` so multi-file uploads land in the same buffer and flush together. Three surfaces apply the same invariant:
 
 | Surface | Buffer key | Trigger |
@@ -105,6 +115,7 @@ Every channel must implement the base interface:
 | `WebhookChannel` | Webhook HTTP handler mounting | Facebook, Feishu/Lark, Pancake |
 | `ReactionChannel` | Status reactions on messages | Telegram, Slack, Feishu |
 | `BlockReplyChannel` | Override gateway block_reply setting | Discord, Feishu/Lark, Pancake, Slack, Zalo OA, Zalo Personal |
+| `ChatBehaviorChannel` | Override gateway chat_behavior setting | Bitrix24, Discord, Feishu/Lark, Pancake, Slack, Telegram, WhatsApp, Zalo OA, Zalo Personal |
 
 `BaseChannel` provides a shared implementation that all channels embed: allowlist matching, `HandleMessage()`, `CheckPolicy()`, and user ID extraction.
 

docs/project-changelog.md

@@ -6,6 +6,27 @@ Significant changes, features, and fixes in reverse chronological order.
 
 ## 2026-05-29
 
+### Human-like channel delivery MVP (issue #67)
+
+**New**
+
+- Added `gateway.chat_behavior` runtime config for global quick acknowledgement and safe final multi-message splitting.
+- Added per-channel `chat_behavior` override support for channel instances that already participate in channel delivery settings.
+- Quick acknowledgements are emitted only for non-streaming channel runs and are cancelled when a block reply or terminal event arrives.
+- Final splitting applies only to non-streaming text-only final replies; unsafe Markdown, code, tables, lists, quotes, JSON, and URL-only paragraphs stay as one message.
+- Added `chat_behavior.preview` RPC plus dashboard controls and per-channel override fields.
+
+**Validation**
+
+- Added Go coverage for config resolution, preview, conservative splitting, and non-streaming quick acknowledgement delivery.
+- Verified focused Go packages, both Go builds, `go vet`, web Vitest, web production build, and `git diff --check`.
+
+**Out of scope**
+
+- No archive/timeline storage, renderer, share/export, or interleaved run history changes. Those remain issue #76 scope.
+
+---
+
 ### GitHub Releases update scratch dir fallback (issue #94)
 
 - Changed GitHub Releases package updates to prefer `{runtimeDir}/tmp` for