fix: overview reflects page deletions - #585

…ont, worker+timeout) — phase A docmost#586

Phase A of docmost#585 (unblocks phase B docmost#588): rasterize SVG (schematic .drawio.svg
and svg attachments) to PNG entirely in-process with no browser/service (hard
constraint docmost#423), so the in-app agent can later 'see' diagrams.

- New apps/server/src/integrations/ai/rasterize/ module: rasterizeSvgToPng(svg,
  opts) runs resvg-wasm in a long-lived worker thread with a per-job wall-clock
  timeout that terminates+recreates the worker (sync wasm can't be interrupted
  otherwise) and rejects in-flight jobs race-safely; lazy single wasm+font init;
  input byte cap + longest-side downscale cap; render/encode wrapped in
  try/finally to free wasm memory on the error path too.
- @resvg/resvg-wasm@^2.6 in prod dependencies (not dev, else pnpm --prod prunes
  it); wasm resolved via the exported ./index_bg.wasm subpath (with a '.'-entry
  fallback). Vendored DejaVu Sans (Latin+Cyrillic) + its license as fontBuffers;
  defaultFontFamily 'DejaVu Sans'. nest-cli.json assets copy the ttf+license into
  dist (tsc doesn't); Dockerfile already ships apps/server/dist wholesale.

Co-Authored-By: Claude Opus 4.8 (1M context) <[email protected]>

…ss-provider — phase B docmost#588

Phase B of docmost#585 (stacked on docmost#586 rasterizer): an in-app viewImage({pageId,node})
tool that delivers a page image node to the model AS VISION on any provider.
Raster (png/jpeg/webp/gif) passthrough with a 5 MiB cap; SVG/.drawio.svg
rasterized to PNG via docmost#586. Because openai/openai-compatible stringify a
tool-result image, the image is delivered as an ephemeral user-role message
injected via prepareStep, keyed by toolCallId in a per-run closure Map:
injected on every step after the call (incl. the toolChoice:'none' synthesis
step) until the model has produced text about it, then evicted (inject-then-
delete) so it never starves synthesis nor re-bills forever. The injected
message is never persisted (buildStepParts reads toolResults, not messages),
and the tool's persisted result is a small no-bytes past-tense note so replay
doesn't imply a live image.

Adds a public fetchAttachmentBytes on the mcp client (thin wrapper over the
guarded fetchInternalFile; registered in IMediaMixin / DocmostClientMethod /
DocmostClientLike / the drift-guard). Fail-closed behind AI_CHAT_VIEW_IMAGE
(default false); the same flag gates registration AND injection. forShare
(public-share chat) is untouched, so viewImage is naturally absent there.

Co-Authored-By: Claude Opus 4.8 (1M context) <[email protected]>