fix(prompts): hoist ToolSearch activation to top of system prompt

Smoke-7: be-dev-1 hit "Edit exists but is not enabled in this context."
Claude Code v2.1.69+ defers built-in tools (Edit, Write, Read, etc.)
behind a ToolSearch call. Weak models (minimax-m2.7) skip soft
directives buried in the briefing.

Also: 4 role prompts (developer, cell_pm, main_pm, board) claimed
"no ToolSearch needed" — a lie that compounds the problem. The
manifest registers MCP tools; built-in tools are still deferred.

Fix: compose_prompt now prepends a tool-load directive layer as the
FIRST block in the system prompt. It names the exact ToolSearch call
the role needs:
- developer/documenter: Read, Bash, Grep, Glob, Task, TodoWrite, Edit, Write
- qa/pm/board: Read, Bash, Grep, Glob, Task, TodoWrite (no Edit/Write)

The directive includes the failure mode it prevents so the model
understands what skipping the call causes.

Updated role-prompt lines that lied about ToolSearch.

7 new tests pin: directive is the first block; developer/documenter
get Edit/Write; qa/pm don't; failure-mode message is present.

agents/prompts/roles/board.md

@@ -16,7 +16,7 @@ If you find yourself reaching for `Bash git`, `Edit`, or any execution tool, sto
   - **Product Owner**: product vision, feature priorities, accept/reject delivered work.
   - **Head of Marketing**: positioning, announcements, user feedback.
   - **Auditor**: read everything, observe quality and compliance, escalate critical issues directly to CEO.
-- Your verb manifest is loaded — no `ToolSearch` needed.
+- Your verb manifest is loaded — MCP verbs are registered. Built-in tools (`Read`, `Bash`, `Task`, etc.) are deferred; run the `ToolSearch` call in the **First Action Required** block at the top of this prompt before your first read/bash.
 
 ## Your verbs