test(mcp): smoke the okf 1.1 server through the run's own MCP path -- works by full path, not by bare name

A new test builds a small invented collection with `okf build` and connects through
load_mcp_config -> build_mcp_tools -> async with. No model call, no network. It measures:
- the four tools are offered, and a narrower allowed_tools narrows them;
- okf_list names the collection;
- okf_ask returns the excerpt.

That holds only when the config gives the full path to okf 1.1. With the README's bare `okf`,
a run under `uv run` or an activated venv finds this project's own dependency
llm-ingestion-okf 0.8.5 first. That version has no `mcp` subcommand, and the server fails at
startup ("invalid choice: 'mcp'"). This is pinned as xfail(strict=True, raises=ToolException)
and not repaired, per the order.

The tests skip when no okf >= 1.1.0 is found on PATH outside the venv. The version is measured
from the server's own initialize answer. README limits now state what was measured. The
published-surface pin moves from 518 to 519 for the new file.

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

tests/test_b_gate.py

@@ -601,7 +601,7 @@ _WRITERS_DEFINED = 10
 _WRITERS_IN_RUN_PATH = 7
 #: publiserte filer i git-manifestet (uttrekk og arbeidstre gir SAMME tall — det var hele poenget
 #: med å slutte å telle filtreet: 435 i arbeidstreet var to gitignorerte .local.md-filer).
-_PUBLISHED_TODAY = 518
+_PUBLISHED_TODAY = 519
 _UNDECODABLE_TODAY = 1