fix(tools): honour select fields in b24_task_list — task body was unreachable

[aa-blinov]

Summary

Fixes #203 — b24_task_list accepted a select, passed it to Bitrix24 correctly, and then threw away everything outside the default seven fields, so a task's body could not be read through this MCP at all. description now comes back when it's in the select (with Bitrix24's descriptionInBbcode markup flag), and so do the select-only scalars groupId / createdBy / parentId / changedDate / closedDate.

Type of change

• feat
• fix
• docs
• chore
• test
• refactor
• ci

Linked issue

Closes #203

Checklist

• PR title follows Conventional Commits
• pnpm lint passes
• pnpm typecheck passes
• pnpm test passes
• New or changed code has tests
• Public-facing changes reflected in docs/ and skills/ (README tool table + the b24_task_list tool description; the tool-authoring conventions are unchanged, so docs/ADDING-TOOLS.md and the agent skill need no edit)
• No unrelated changes
• No secrets in code, tests, or CI logs

Screenshots / logs

Live portal, same task, before and after. With the field selected:

{"total":1,"returned":1,"tasks":[{"id":"4153","title":"…","description":"[b]Причина[/b]\n\n…","descriptionInBbcode":true,"groupId":"111","createdBy":"35"}]}

Default listing, unchanged (no new keys, no extra bytes):

{"total":null,"returned":1,"tasks":[{"id":"4153","title":"…","status":"2","deadline":null,"responsibleId":"9","createdDate":"…","priority":"1"}]}

The body in that first response is 764 characters; nothing is truncated.

Notes for reviewers

The bug was entirely in the projection, not the transport. normalizeBitrix24Select did its job and tasks.task.list returned the field — toTaskShort then rebuilt each row from a fixed field list, so the select looked honoured while the data quietly vanished. Worth knowing because the same shape applies to any field a future PR wants to surface.

Two decisions I'd particularly like a second opinion on:

Why the body is opt-in but the scalars aren't. Bitrix24 omits groupId / createdBy / parentId / changedDate / closedDate unless they're selected, so "present on the wire" is already equivalent to "the operator asked for it" — projecting them when present is honouring the select, no flag needed. description is different: toTaskShort is shared with create / update / rate and the seven lifecycle verbs, and Bitrix24 echoes the full task on those endpoints. Projecting the body unconditionally would bill the agent for a description it had just written, on every mutation. Hence ToTaskShortOptions.withDescription, which only the read path sets.

What I left dropped on purpose. Bitrix24 ships nested group and creator objects alongside groupId / createdBy without being asked — member counts, work positions, avatar URLs. Those stay out of the projection; if someone wants the group name, groupId plus a group tool is the cheaper path. There's a test pinning this so it doesn't drift back in.

Issue #203 also mentions the absence of a single-task get tool. I didn't add one here — with filter: { id: N } plus a select the list tool now covers the "what is this task about" case, and a b24_task_get on v3 is a separate decision (it's the worked example in skills/manage-bx24-template-mcp/adding-tools.md but has never shipped). Happy to do it as a follow-up if you'd rather have the dedicated tool.

Unrelated to this PR but same reporter, in case it's useful triage: #203 also lists createdBy and groupId, which this covers, and the reporter's other open issue (#205) is a separate matter.