Official 1.2.0 version

ver. 1.2.0

The user can hand the assistant a document. A paper clip next to the question box takes a
PDF, an image or a text file, and the model reads it - which, together with an action, is a
PDF filling a form without anybody retyping what is in it.

• Attachments (HelpChatAI.Attachments, RTL): .pdf and .png .jpg .jpeg .gif .webp
  travel as bytes in the block each API wants (Anthropic document/image, OpenAI a file
  part and an image_url data URI, Gemini inlineData); .txt .md .csv .json .xml .log .ini .yaml .yml are decoded when they arrive - BOM, else UTF-8, else the ANSI code page -
  and put in front of the question, fenced so the content of a file cannot read as an
  instruction. A .docx or an .xlsx is refused by name: no model reads one, and
  sending it anyway would look like it worked
• The paper clip, or a file dropped on the panel - anywhere on it, and more than one at
  a time. A chip per document above the question box, with the glyph of its kind, its size
  and an ✕, and a turning ring while the bytes go up
• Off until you turn it on: Settings.Attachments.Enabled is False, because what the
  user attaches leaves the machine. MaxCount, MaxSizeKB and MaxTotalKB bound the rest.
  The clip appears only when attachments are enabled and the configured provider can read
  documents, so docsearch and stub never promise what their answer could not deliver
• An attachment belongs to the conversation, not to the question: it is sent again with
  every later question, so a second question about the same document needs no second upload,
  and ↺ takes the documents away with the conversation. They live in memory and are never
  written to the conversation file on disk
• The panel draws the chips from the server (GET /api/attachments), not from its own
  memory: a page reload - a VCL style change recreates the window and reloads it - used to
  leave the bar empty while the documents kept going out with every question
• The file-type glyphs are inline SVG in the panel page (Material Design Icons,
  Apache 2.0): generic glyphs, no brand logo, and nothing new to ship
• CRM Demo\Docs holds two documents to try it with - a request for information as a PDF
  and the notes of the follow-up call - and both demos accept attachments. Attach the PDF,
  ask "create a lead from the attached request", and the model fills create_lead with
  what it read
• 271 tests, 25 of them new: the accepted and refused types, the three limits, text
  decoding, the blocks each of the three providers builds, and the endpoints over real HTTP