feat: unify poll support

Co-authored-by: DBH <5251425+dbhurley@users.noreply.github.com>

docs/poll.md

@@ -0,0 +1,52 @@
+---
+summary: "Poll sending via gateway + CLI"
+read_when:
+  - Adding or modifying poll support
+  - Debugging poll sends from the CLI or gateway
+---
+# Polls
+
+Updated: 2026-01-06
+
+## Supported providers
+- WhatsApp (web provider)
+- Discord
+
+## CLI
+
+```bash
+# WhatsApp
+clawdbot poll --to +15555550123 -q "Lunch today?" -o "Yes" -o "No" -o "Maybe"
+clawdbot poll --to 123456789@g.us -q "Meeting time?" -o "10am" -o "2pm" -o "4pm" -s 2
+
+# Discord
+clawdbot poll --to channel:123456789 -q "Snack?" -o "Pizza" -o "Sushi" --provider discord
+clawdbot poll --to channel:123456789 -q "Plan?" -o "A" -o "B" --provider discord --duration-hours 48
+```
+
+Options:
+- `--provider`: `whatsapp` (default) or `discord`
+- `--max-selections`: how many choices a voter can select (default: 1)
+- `--duration-hours`: Discord-only (defaults to 24 when omitted)
+
+## Gateway RPC
+
+Method: `poll`
+
+Params:
+- `to` (string, required)
+- `question` (string, required)
+- `options` (string[], required)
+- `maxSelections` (number, optional)
+- `durationHours` (number, optional)
+- `provider` (string, optional, default: `whatsapp`)
+- `idempotencyKey` (string, required)
+
+## Provider differences
+- WhatsApp: 2-12 options, `maxSelections` must be within option count, ignores `durationHours`.
+- Discord: 2-10 options, `durationHours` clamped to 1-768 hours (default 24). `maxSelections > 1` enables multi-select; Discord does not support a strict selection count.
+
+## Agent tool (Discord)
+The Discord tool action `poll` still uses `question`, `answers`, optional `allowMultiselect`, `durationHours`, and `content`. The gateway/CLI poll model maps `allowMultiselect` to `maxSelections > 1`.
+
+Note: Discord has no “pick exactly N” mode; `maxSelections` is treated as a boolean (`> 1` = multiselect).