release(v5.10.1): drop gemini-bridge from the pipeline; correct the T1 §6 PoC status

gemini-bridge is dropped by operator directive (three repetitions). The drop is
permanent, not a wait-for-SDK-upgrade state, so the change clears every LIVE
surface that could still steer a run toward the agent and leaves the historical
record alone.

Live surfaces cleared: agents/gemini-bridge.md deleted; trekresearch (bridge
launch block, --local help, high-effort always-on pair, stats record,
degradation list), trekplan, trekbrief, research-orchestrator (mode table,
agent table, prompting block, summary line), README (feature prose, mode table,
agent prose, mermaid EXTERNAL node, conditional legend, optional-MCP
requirement, --local section), CLAUDE.md, settings.json (the whole
trekresearch.geminiBridge block), both templates, architecture.md,
command-modes.md.

trekplan high-effort Adversarial Pass 2 now degrades EXPLICITLY: it emits its
section with status "unavailable, skipped" instead of failing or vanishing. A
high-effort plan carrying no Pass 2 marker is indistinguishable from one whose
Pass 2 crashed, which is the failure mode this wording exists to prevent.

gemini_used is deliberately KEPT as a vestigial trekresearch stats field pinned
to false. Removing it would break the observability export schema for existing
consumers, and the directive was about the agent, not the field.

Not touched: CHANGELOG history and the measurement/decision docs keep their
gemini references. They record what a past version did or what was measured
then; rewriting them is the same defect class as bumping a version string
inside a measurement doc.

Driven test-first. Five new pins in tests/lib/doc-consistency.test.mjs, verified
RED before the edits, including a KNOWN-POSITIVE CONTROL asserting the
historical records still DO carry gemini references — so the empty result on
live surfaces is a measurement and not a broken query (Verifiseringsloven
ansikt 4). Agent inventory 24 -> 23 (20 spawnable + 3 orchestrator reference
docs); the <example>-block floor moves 34 -> 32 because an agent legitimately
left the inventory, not because examples went missing from a surviving one.

Docs: docs/T1-cc26-delegated-orchestration.md §8 item 3 claimed both the §6
synthesis-agent PoC and the §5 bake-off were "designed but unbuilt". That was
written in S7 and falsified the same afternoon by S12, which ran the §6 PoC and
recorded Δ main-context (faithful flow) = 0.0%, NEGATIVE. The stale wording is
what caused the settled PoC to be re-ordered as new work on 2026-09-02, so it is
struck rather than deleted and §6 gained a RUN AND DECLINED status block. The
finding is structural, not stochastic: Phase 5 spawns the exploration swarm
foreground (trekplan.md:158,338-341), so the outputs are already resident in
main before Phase 7 — delegating only the Phase-7 digest evicts nothing.

Also measured 2026-09-03 (CC 2.1.259): claude -p --output-format stream-json
runs on subscription auth with no ANTHROPIC_API_KEY and now emits a
subagent_stats block, so S12's environment-block premise is half stale. Recorded
in §8 item 4. It lowers the cost of §5; it changes nothing about §6.

Suite 1041 (1039/0/2), up from 1036 by exactly the five tests added.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

agents/research-orchestrator.md

@@ -61,13 +61,16 @@ Execute these phases in order. Do not skip phases.
 
 Based on the mode, determine which agent groups to launch:
 
-| Mode | Local agents | External agents | Gemini bridge |
-|------|-------------|-----------------|---------------|
-| `default` | Yes | Yes | Yes (if enabled in settings) |
-| `local` | Yes | No | No |
-| `external` | No | Yes | Yes (if enabled) |
+| Mode | Local agents | External agents |
+|------|-------------|-----------------|
+| `default` | Yes | Yes |
+| `local` | Yes | No |
+| `external` | No | Yes |
 | `quick` | N/A — handled inline by the command, not the orchestrator |
 
+> **No bridge agent (v5.10.1).** The third-party second-opinion bridge was dropped
+> by operator directive; there is no bridge column to select.
+
 **Local agents** (reuse existing plugin agents with research-focused prompts):
 
 | Agent | Purpose in research context |
@@ -87,12 +90,6 @@ Based on the mode, determine which agent groups to launch:
 | `security-researcher` | CVEs, audit history, supply chain risks |
 | `contrarian-researcher` | Counter-evidence, overlooked alternatives, reasons to reconsider |
 
-**Bridge agent:**
-
-| Agent | Purpose |
-|-------|---------|
-| `gemini-bridge` | Independent second opinion via Gemini Deep Research |
-
 ### Phase 2 — Parallel research
 
 Launch ALL selected agents **in parallel** using the Agent tool — one message,
@@ -127,11 +124,6 @@ Examples:
 Pass the research question, specific dimensions to investigate, and any context from
 the interview about what the user already knows or cares about.
 
-**Prompting gemini-bridge:**
-
-Pass the research question as-is. Do NOT pre-bias with findings from other agents —
-the value of Gemini is independence.
-
 ### Phase 3 — Targeted follow-ups
 
 Review all agent results. Identify knowledge gaps — areas where findings are thin,
@@ -195,7 +187,7 @@ When done, your output message should contain:
 **Brief:** {brief path}
 **Confidence:** {overall confidence 0.0-1.0}
 **Dimensions:** {N} researched
-**Agents:** {N} local + {N} external + {gemini status}
+**Agents:** {N} local + {N} external
 
 ### Key Findings
 - {Finding 1}
@@ -226,7 +218,7 @@ You can:
 - **Sources:** Every claim in the brief must cite a source (URL or file path).
   Never invent findings.
 - **Honesty:** If a question is trivially answerable, say so. Don't inflate research.
-- **Graceful degradation:** If MCP tools are unavailable (Tavily, Gemini), proceed
+- **Graceful degradation:** If MCP tools are unavailable (Tavily, MS Learn), proceed
   with available tools and note the limitation in the brief metadata.
 - **Independence:** Do not pre-bias external agents with local findings or vice versa.
   The value is in independent perspectives that are THEN triangulated.