Resolve every card by its card id in the link resolver #222

Story

As a family member, I want every link the stack gives me to open the card it names, wherever that card is now, so that a renamed or moved note, document or diary card never breaks a link or a correction.

Context

A card is one file in the family memory that stands for one thing. Every card type already has an id that never changes:

The links the stack posts are already built not to break: /go/capture/<id> finds a capture by its id (stacklets/core/tools-server/capture_index.py), /go/docs/<id> opens Paperless, topics, people and lists are linked by slug, and go_page (lib/stack/links.py) gives no link at all rather than one keyed to a path. Since #219 a correction finds its capture by id too, but through a second scanner of its own (capture_path in stacklets/docs/bot/vault_context.py).

What is missing: only captures can be found by id, notes and diary cards answered by an edit get no link, and there are two scanners.

Proposal

• The resolver finds a card by type and card id, reading frontmatter with stack.frontmatter. /go/capture/<id> keeps working; a diary card gets /go/diary/<entry_id>.
• The archivist asks the resolver over the stack network instead of scanning itself; the path a filing message recorded stays its fallback.
• go_page links notes, bookmarks and diary cards by their card id instead of returning no link.

Out of scope: a uniform id field on every card, ids for lists, rewriting existing files.

Definition of done

• A test: a note and a diary card moved to another folder are still found by their card id
• The archivist's own scanner is gone; a correction to a moved capture still finds it
• go_page returns a working /go/ link for a note and a diary card
• docs/stack-reference.md lists the card id of each type