Adds a new **Enable Coder Agents** section to the Early Access doc
explaining how to activate the `agents` experiment flag via
`CODER_EXPERIMENTS` or `--experiments`.
## Changes
### `docs/ai-coder/agents/early-access.md`
- New **Enable Coder Agents** section with env var and CLI flag
examples.
- Note that the `agents` flag is excluded from wildcard (`*`) opt-in.
- Quick-start checklist: dashboard → Admin → configure provider/model →
start chatting.
- Link to GitHub issues for feedback.
### `docs/ai-coder/agents/index.md`
- Updated **Product status** from "internal preview" to "Early Access"
with a link to the early-access page for enablement instructions.
## Changes
- Add `"state": ["early access"]` to all child pages under Coder Agents
in `docs/manifest.json` (Architecture, Models, Platform Controls, Early
Access).
- Point the Coder Agents video `<source>` directly at
`raw.githubusercontent.com` instead of the `github.com/blob/` URL with
`?raw=true`.
Adds a new child page at `/docs/ai-coder/agents/early-access` describing
the Coder Agents Early Access, including what it includes, what it does
not include, feature scope, licensing, and how to provide feedback.
This change adds support for image attachments to chat via add button
and clipboard paste. Files are stored in a new `chat_files` table and
referenced by ID in message content. File data is resolved from storage
at LLM dispatch time, keeping the message content column small.
Upload validates MIME types via content type or content sniffing against
an allowlist (png, jpeg, gif, webp). The retrieval endpoint serves files
with immutable caching headers. On the frontend, uploads start eagerly
on attach with a background fetch to pre-warm the browser HTTP cache so
the timeline renders instantly after send.
Matt Vollmer