docs(research): refresh fallow.md + scan against current ship state (#36)

* docs(research): refresh fallow.md + scan against current ship state

fallow.md gains a "Status snapshot (as of 2026-05-01)" section that
tabulates every adoption candidate's ship status — single source of
truth for "what's open" without munging the original tier tables.

Captures:
- Tier A all shipped (PR #26)
- B.5 partial (v1 in PR #33; --base <ref> + verdict deferred to v1.x)
- B.6 shipped (PR #30) — table-in-DB, not parallel JSON files
- B.7 shipped (PR #28) — landed on `symbols`, not `exports`
- B.8 / C.9 / C.10 / C.11 / D.* still as-was
- MCP server (agent-transports v1) shipped in PR #35 (adjacent —
  not a numbered fallow candidate but worth surfacing here)

§ 6 open questions: marks the 2 settled ones (actions ownership,
audit verdict default) with their resolution PRs; preserves the 2
still-open ones (coverage column shape, plugin layer scope).

§ 3 already-shipped block: updates the visibility-tags note to
acknowledge B.7 promoted it from regex to structured column instead
of saying "B.7 proposes promoting" (which it doesn't anymore).

competitive-scan-2026-04.md § 4: marks MCP server wrapping `query`
as ✅ shipped via PR #35 with a cross-link to fallow.md's status
snapshot. Other items still tracked there.

No behavior change; pure docs refresh to match current reality.

* docs(research): fix MD056 — D row in fallow.md status snapshot was 4 cells, header was 5

CodeRabbit caught: status-snapshot table header has 5 columns (Tier / # / Item / Status / Where) but the D.12-D.16 row only had 4 (collapsed Status + Where into one cell). Markdown parses that as a malformed table; renderers either drop the row or misalign neighbouring rows. Added the missing 5th cell pointing back at § 1's Defer / skip table for the per-row reasoning.

* docs(research): align B.7 row title to shipped column name (symbols.visibility)

CodeRabbit caught: Tier B table B.7 row title still said 'exports.visibility column' despite the body hedging '(or symbols)' AND the shipped column landing on symbols. Status snapshot row at L22 already says symbols. Updated the title to match shipped reality + added an explicit nod to the original hedge so the historical-record property survives.

Author: SutuSebastian

docs/research/competitive-scan-2026-04.md

@@ -66,14 +66,14 @@ All shipped under PR [#23](https://github.com/stainless-code/codemap/pull/23) as
 
 ## 4. What moved to the roadmap
 
-Items the scan called out as "watch / defer / future" that are now tracked in [docs/roadmap.md § Backlog](../roadmap.md#backlog) — go there for the latest status, not here:
-
-- MCP server wrapping `query`
-- HTTP API (`codemap serve`)
-- Recipes-as-content registry + project-local recipes (`.codemap/recipes/`)
-- Targeted-read CLI (`codemap show <symbol>`)
-- Watch mode (`codemap watch`)
-- Cross-agent handoff artifact (speculative)
+Items the scan called out as "watch / defer / future" — most still live in [docs/roadmap.md § Backlog](../roadmap.md#backlog); items shipped after this scan are linked to their PRs.
+
+- ✅ **MCP server wrapping `query`** — shipped as `codemap mcp` (agent-transports v1) in PR [#35](https://github.com/stainless-code/codemap/pull/35). Tool taxonomy, output shape, and resource catalog reserved for HTTP API to inherit. See [`research/fallow.md` § Status snapshot](./fallow.md#status-snapshot-as-of-2026-05-01) for the full ship summary.
+- HTTP API (`codemap serve`) — still backlog
+- Recipes-as-content registry + project-local recipes (`.codemap/recipes/`) — still backlog
+- Targeted-read CLI (`codemap show <symbol>`) — still backlog
+- Watch mode (`codemap watch`) — still backlog
+- Cross-agent handoff artifact (speculative) — still backlog
 
 The scan's "PASS" list (dead-code / dupes / complexity / boundaries / fix actions, runtime/V8 coverage merging, framework plugins, PageRank summarization, skyline visualization, daemon process, embedded intent classification) has been folded into [roadmap.md § Non-goals](../roadmap.md#non-goals-v1) — that's the canonical home; do not duplicate here.