v0.8.0: enumerate MCP tools explicitly in tools:/allowed-tools: (#1)

A trailing mcp__…__* wildcard in an agent's tools: / a skill's
allowed-tools: does not expand — verified by spawning the companion
agent, which saw zero mcp__ tools despite the parent session having
all 19 connected. Working plugins (cluster) enumerate every MCP tool
by full name; do the same here.

- agents/companion.md, skills/*: tools:/allowed-tools: now list all 19
  mcp__plugin_nvim-agentic-companion_neovim__vim_* tools explicitly
- companion.md: drop the stale nvim-mcp-repin.path/.service reference
  (re-pin is now the bridge's ExecStartPost); spell out the launch-race
  (issue #2) in the unavailability runbook

Fixes #1. Refs #2.

agents/companion.md

@@ -2,7 +2,7 @@
 name: companion
 description: Neovim companion — answers questions about the user's *running* nvim instance and acts inside it on their behalf. Uses `vim_*` tools to introspect live state (buffers, keymaps, diagnostics, loaded plugins, cursor position) and to execute `:` commands / lua. Reads the declarative NixVim config as the source-of-truth for "what *should* be there." For buffer-editing work, hands off to the in-editor `coder/claudecode.nvim` session instead of duplicating it. Trigger on <!-- BEGIN ROUTING TRIGGERS -->"how do I do X in nvim", "what's mapped to", "open file finder in nvim", "what plugin handles", "in my neovim", "nvim companion", "drive my nvim", "introspect nvim", "where is this keymap defined", "what's bound to <leader>"<!-- END ROUTING TRIGGERS -->.
 color: green
-tools: Bash, Read, Edit, Write, Glob, Grep, Skill, AskUserQuestion, WebFetch, WebSearch, TodoWrite, mcp__plugin_nvim-agentic-companion_neovim__*
+tools: Bash, Read, Edit, Write, Glob, Grep, Skill, AskUserQuestion, WebFetch, WebSearch, TodoWrite, mcp__plugin_nvim-agentic-companion_neovim__vim_buffer, mcp__plugin_nvim-agentic-companion_neovim__vim_buffer_save, mcp__plugin_nvim-agentic-companion_neovim__vim_buffer_switch, mcp__plugin_nvim-agentic-companion_neovim__vim_command, mcp__plugin_nvim-agentic-companion_neovim__vim_edit, mcp__plugin_nvim-agentic-companion_neovim__vim_file_open, mcp__plugin_nvim-agentic-companion_neovim__vim_fold, mcp__plugin_nvim-agentic-companion_neovim__vim_grep, mcp__plugin_nvim-agentic-companion_neovim__vim_health, mcp__plugin_nvim-agentic-companion_neovim__vim_jump, mcp__plugin_nvim-agentic-companion_neovim__vim_macro, mcp__plugin_nvim-agentic-companion_neovim__vim_mark, mcp__plugin_nvim-agentic-companion_neovim__vim_register, mcp__plugin_nvim-agentic-companion_neovim__vim_search, mcp__plugin_nvim-agentic-companion_neovim__vim_search_replace, mcp__plugin_nvim-agentic-companion_neovim__vim_status, mcp__plugin_nvim-agentic-companion_neovim__vim_tab, mcp__plugin_nvim-agentic-companion_neovim__vim_visual, mcp__plugin_nvim-agentic-companion_neovim__vim_window
 ---
 
 # nvim companion
@@ -192,14 +192,17 @@ alone. The path has three links that can each break — walk them in
 order when telling the user what to check:
 
 1. **nvim** — is it running, and did it create the socket at
-   `{{nvim_socket}}`? (`ls` it.) No socket ⇒ restart nvim. On a nvim
-   restart the socket-appearance inotify event re-pins the pool
-   automatically (`nvim-mcp-repin.path` → `.service`).
+   `{{nvim_socket}}`? (`ls` it.) No socket ⇒ restart nvim. The socket's
+   appearance is what starts the bridge (`nvim-mcp-bridge.path`, an
+   inotify watch); the bridge's own `ExecStartPost` then re-pins the
+   pool. No separate repin unit.
 2. **bridge / pool** — if the socket exists but tools are absent,
    `systemctl status nvim-mcp-bridge` and the pool status at
    `http://127.0.0.1:12010/pools/neovim` are the next suspects.
-3. **This session** — MCP servers attach at `claude` launch. A session
-   started before the wiring landed never picks it up; restart Claude
-   Code.
+3. **This session** — MCP servers attach **once, at `claude` launch**,
+   and a failed handshake is not retried. A session started while the
+   bridge upstream was still coming up (e.g. seconds after a nvim
+   restart) never registers the `vim_*` tools — restart Claude Code
+   once the bridge reads `active`.
 
 Do not pretend to introspect when you can't.