refactor: extract kb_framework package, build graph in memory

Scripts become thin CLIs over kb_framework (graph, query, query_tools,
vault, instructions) so the hosted read-only connector shares one
implementation with the stdio server. The MCP server builds the graph
from Markdown on demand and invalidates it on writes; refresh_graph
rebuilds in memory and reports validation problems. Pre-commit hook
validates only; index/graph.json is no longer read, written or staged
(generate-graph.py --write remains for operators). Golden fixtures pin
graph and tool payloads to the previous output. Agent and skill docs
updated to match.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

kb_framework/instructions.py

@@ -0,0 +1,35 @@
+"""Locate and read the framework's agent instructions.
+
+`read_instructions` returns AGENTS.md and AGENT_QUERY_GUIDE.md so an agent
+whose only access is MCP still gets the operating rules. In a source checkout
+the documents live next to this package (the framework root); in an installed
+wheel they are bundled under `kb_framework/_docs/`. Both lookups are explicit —
+there is never a fallback to files inside the data vault.
+"""
+
+from __future__ import annotations
+
+from pathlib import Path
+from typing import Any, Dict
+
+DOCUMENT_NAMES = ("AGENTS.md", "AGENT_QUERY_GUIDE.md")
+_PACKAGE_DIR = Path(__file__).resolve().parent
+# Source checkout: the framework repository root (parent of this package).
+FRAMEWORK_ROOT = _PACKAGE_DIR.parent
+_BUNDLED_DOCS = _PACKAGE_DIR / "_docs"
+
+
+def instructions_root() -> Path:
+    """Directory holding the instruction documents for this installation."""
+    if (FRAMEWORK_ROOT / DOCUMENT_NAMES[0]).is_file():
+        return FRAMEWORK_ROOT
+    return _BUNDLED_DOCS
+
+
+def read_instructions() -> Dict[str, Any]:
+    root = instructions_root()
+    documents = [
+        {"path": name, "content": (root / name).read_text(encoding="utf-8")}
+        for name in DOCUMENT_NAMES
+    ]
+    return {"framework_root": str(root), "documents": documents}