docs(cryptify): document notifyRecipients on /fileupload/init

[dobby-coder]

Closes #41.

What changed

docs/repos/cryptify.md API section:

• The single-line description of POST /fileupload/init was inaccurate (listed sender email and file size, which are not in the request body) and missing two parameters: confirm and the new notifyRecipients from cryptify#135.
• Replaced the bullet's parenthetical with a complete request-body table listing every field, its type, whether it is required, and what it does.
• Reworded the finalize bullet from "send the notification email" to "sends the recipient notification email if notifyRecipients was true on init", which matches the post-PR-135 behaviour.
• Added a back-compat note: server defaults notifyRecipients to true when the field is omitted on the wire; SDK clients (@e4a/pg-js 1.2.0+, E4A.PostGuard 0.3.0+) send false explicitly to keep silent-by-default semantics regardless of cryptify version.
• Pinned a [Source: api-description.yaml#L33-L72] link at the post-merge cryptify hash 723c8db1.

The rest of the API section was skimmed for other phrasing that assumed the recipient mail always fires; only the finalize line needed touching.

Verification

• npm run docs:build is green (10s build, no warnings beyond the pre-existing chunk-size note).
• Spot-checked docs/.vitepress/dist/repos/cryptify.html for notifyRecipients and fileupload/init. Both render.
• Verified the source URL returns 200 and that the line range still contains the /fileupload/init request body at the pinned hash.

Reviewer quickstart

git fetch origin && git checkout docs/cryptify-notify-recipients && npm install && npm run docs:dev

Then open /repos/cryptify and check the new request-body table under ## API.