fix: scope history injection to pending-only

docs/channels/whatsapp.md

@@ -202,9 +202,9 @@ The wizard uses it to set your **allowlist/owner** so your own DMs are permitted
   - `always`: always triggers.
 - `/activation mention|always` is owner-only and must be sent as a standalone message.
 - Owner = `channels.whatsapp.allowFrom` (or self E.164 if unset).
-- **History injection**:
-  - Recent messages (default 50) inserted under:
-    `[Chat messages since your last reply - for context]`
+- **History injection** (pending-only):
+  - Recent *unprocessed* messages (default 50) inserted under:
+    `[Chat messages since your last reply - for context]` (messages already in the session are not re-injected)
   - Current message under:
     `[Current message - respond to this]`
   - Sender suffix appended: `[from: Name (+E164)]`

docs/concepts/group-messages.md

@@ -13,7 +13,7 @@ Note: `agents.list[].groupChat.mentionPatterns` is now used by Telegram/Discord/
 - Activation modes: `mention` (default) or `always`. `mention` requires a ping (real WhatsApp @-mentions via `mentionedJids`, regex patterns, or the bot’s E.164 anywhere in the text). `always` wakes the agent on every message but it should reply only when it can add meaningful value; otherwise it returns the silent token `NO_REPLY`. Defaults can be set in config (`channels.whatsapp.groups`) and overridden per group via `/activation`. When `channels.whatsapp.groups` is set, it also acts as a group allowlist (include `"*"` to allow all).
 - Group policy: `channels.whatsapp.groupPolicy` controls whether group messages are accepted (`open|disabled|allowlist`). `allowlist` uses `channels.whatsapp.groupAllowFrom` (fallback: explicit `channels.whatsapp.allowFrom`). Default is `allowlist` (blocked until you add senders).
 - Per-group sessions: session keys look like `agent:<agentId>:whatsapp:group:<jid>` so commands such as `/verbose on` or `/think high` (sent as standalone messages) are scoped to that group; personal DM state is untouched. Heartbeats are skipped for group threads.
-- Context injection: last N (default 50) group messages are prefixed under `[Chat messages since your last reply - for context]`, with the triggering line under `[Current message - respond to this]`.
+- Context injection: **pending-only** group messages (default 50) that *did not* trigger a run are prefixed under `[Chat messages since your last reply - for context]`, with the triggering line under `[Current message - respond to this]`. Messages already in the session are not re-injected.
 - Sender surfacing: every group batch now ends with `[from: Sender Name (+E164)]` so Pi knows who is speaking.
 - Ephemeral/view-once: we unwrap those before extracting text/mentions, so pings inside them still trigger.
 - Group system prompt: on the first turn of a group session (and whenever `/activation` changes the mode) we inject a short blurb into the system prompt like `You are replying inside the WhatsApp group "<subject>". Group members: Alice (+44...), Bob (+43...), … Activation: trigger-only … Address the specific sender noted in the message context.` If metadata isn’t available we still tell the agent it’s a group chat.

docs/concepts/groups.md

@@ -221,7 +221,7 @@ Notes:
 - Per-agent override: `agents.list[].groupChat.mentionPatterns` (useful when multiple agents share a group).
 - Mention gating is only enforced when mention detection is possible (native mentions or `mentionPatterns` are configured).
 - Discord defaults live in `channels.discord.guilds."*"` (overridable per guild/channel).
-- Group history context is wrapped uniformly across channels; use `messages.groupChat.historyLimit` for the global default and `channels.<channel>.historyLimit` (or `channels.<channel>.accounts.*.historyLimit`) for overrides. Set `0` to disable.
+- Group history context is wrapped uniformly across channels and is **pending-only** (messages skipped due to mention gating); use `messages.groupChat.historyLimit` for the global default and `channels.<channel>.historyLimit` (or `channels.<channel>.accounts.*.historyLimit`) for overrides. Set `0` to disable.
 
 ## Group allowlists
 When `channels.whatsapp.groups`, `channels.telegram.groups`, or `channels.imessage.groups` is configured, the keys act as a group allowlist. Use `"*"` to allow all groups while still setting default mention behavior.

docs/concepts/messages.md

@@ -85,6 +85,10 @@ When a channel supplies history, it uses a shared wrapper:
 - `[Chat messages since your last reply - for context]`
 - `[Current message - respond to this]`
 
+History buffers are **pending-only**: they include group messages that did *not*
+trigger a run (for example, mention-gated messages) and **exclude** messages
+already in the session transcript.
+
 Directive stripping only applies to the **current message** section so history
 remains intact. Channels that wrap history should set `CommandBody` (or
 `RawBody`) to the original message text and keep `Body` as the combined prompt.