chore(cleanup): R-b R3 — profiles, phase signals and the effort dialog removed, one fixed path per command

The four profiles, the resolver, the profile validator and docs/profiles.md go;
/trekbrief Phase 3.5 and the brief's phase_signals checks go (an older brief's
key is ignored); MANIFEST_PROFILE_DRIFT and profile_used go. Every Profile,
Composition rule, Sequencing gate and High-effort section leaves the commands.
Decision 209: /trekresearch runs the full swarm with contrarian-researcher as
wave 2 every run; /trekreview and the coordinator run all four passes with no
high-effort normalization. Voyage agents are spawned with no model (their own
model: opus applies); the two built-in spawns pass model "opus". --profile
stays in the parser as a retired flag that swallows its value. §Model & effort
moves to docs/architecture.md; the sequencing-gate eval case goes.

Files removed: 44 (43 from the R3 list + tests/commands/trekreview.test.mjs,
whose every test pinned removed text). Files edited: 43.
Tests: 2467 (2466 pass / 0 fail / 1 skipped) before, 2309 (2309 pass / 0 fail /
0 skipped) after. Durable check: all three groups green, none pending.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

tests/validators/brief-ceremony.test.mjs

@@ -27,7 +27,6 @@ project_dir: .claude/projects/2026-10-06-dark-mode-toggle/
 research_topics: 0
 research_status: complete
 framing: new-direction
-phase_signals_partial: true
 ${extra}---
 
 # Task