heph.nvim: task views — next/list/capture/attention/state/log (slice 11b)

Backend: enrich `list` to return titled RankedTask rows (title +
canonical_context_id, via a shared ranked_from_row with `next`), so the
Organizational view needs no N+1 node.get. TDD: query_surface test asserts
list rows carry title + context id.

Plugin:
- view.lua: Tactical `next` + Organizational `list` rendered scratch buffers;
  <CR> opens the row's canonical-context doc. Narrowed the node autocmd to
  heph://node/* so view buffers (heph://next, heph://list) don't trip it.
- task.lua: capture, set-attention, done/drop, skip, per-task log append, all
  resolving "the current task" from the buffer (a task node, or a context doc
  via its canonical-context backlink).
- picker.lua: vim.ui.select with Telescope auto-upgrade (headless-safe).
- command.lua: :Heph next/list/capture/attention/done/drop/skip/log/search.

e2e: capture→next→open context→add/check checklist→done; recurring
fresh-checklist (complete rolls forward in place, next occurrence all-unchecked
— the §4.4 hard requirement). 6 specs green via `mise run test-nvim`.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

heph.nvim/plugin/heph.lua

@@ -11,7 +11,7 @@ local grp = vim.api.nvim_create_augroup("heph", { clear = true })
 -- `heph://node/<id>` buffers load and save through the daemon (tech-spec §8).
 vim.api.nvim_create_autocmd("BufReadCmd", {
   group = grp,
-  pattern = "heph://*",
+  pattern = "heph://node/*",
   callback = function(ev)
     local ok, err = pcall(require("heph.node").read, ev.buf, ev.match)
     if not ok then
@@ -22,7 +22,7 @@ vim.api.nvim_create_autocmd("BufReadCmd", {
 
 vim.api.nvim_create_autocmd("BufWriteCmd", {
   group = grp,
-  pattern = "heph://*",
+  pattern = "heph://node/*",
   callback = function(ev)
     local ok, err = pcall(require("heph.node").write, ev.buf, ev.match)
     if not ok then