Clarify API docs for triage endpoint and S3 configuration

[creslinux]

Two small documentation clarifications:

1. API.md - The triage endpoint documentation says "Moves a card from triage into a column" which implies it only works for cards in triage. The implementation works for cards in any state, so updated to clarify.

2. docker-deployment.md / kamal-deployment.md - Added CSP_CONNECT_SRC to the S3 configuration section. Without this, browser Content Security Policy blocks direct uploads to S3.