feat(graphify): threshold signal from 200 tracked code files, the banner informs and the user decides

lib/graphify-gate.sh counts tracked code files (graphify's AST extension set, vendored trees excluded) and, from 200 with no graphify-out/graph.json, prints one banner-sized line; session-start shows it with the /graphify hint. Nothing is built, installed or updated: the rule is the user's (BDR-097), grounded in the LRN-162 measurements (AST build 2.3 s, 0 tokens, a query 2 to 3k tokens). Doctrine section and plugin-advisor thresholds follow the same rule; graphify claude install stays rejected. Test: 11 checks. GRAPHIFY_MIN_CODE_FILES overrides the threshold.

lib/graphify-gate.sh

@@ -0,0 +1,41 @@
+#!/usr/bin/env bash
+# graphify-gate.sh — deterministic "propose graphify" signal (BDR-097).
+#
+# Rule (user, 2026-09-24): graphify only from 200 tracked code files. Below,
+# grep + read is cheaper than a graph. The signal INFORMS, the user DECIDES:
+# nothing here builds, installs or updates a graph.
+#
+# Sourced (functions) or executed: `graphify-gate.sh [dir]` prints one short
+# line (banner-sized) and exits 0 when <dir>'s repo passes the threshold and has
+# no graphify-out/graph.json; silent, rc 1 otherwise. GRAPHIFY_MIN_CODE_FILES
+# overrides the threshold (tests).
+
+GRAPHIFY_MIN_CODE_FILES="${GRAPHIFY_MIN_CODE_FILES:-200}"
+# Extensions graphify extracts by AST (tree-sitter): the proxy for "code file".
+GRAPHIFY_CODE_EXT='py|js|mjs|cjs|ts|tsx|jsx|vue|svelte|astro|php|go|rs|java|kt|c|h|cpp|hpp|cc|cs|rb|swift|scala|sh|bash|lua|sql'
+# Vendored trees sometimes committed; never the project's own code.
+GRAPHIFY_VENDOR_DIRS='vendor|node_modules|third_party|dist|build'
+
+# graphify_code_file_count [dir] → tracked code files, vendored trees excluded.
+# Tracked only (git ls-files): gitignored deps and build output never count.
+graphify_code_file_count() {
+  git -C "${1:-.}" ls-files 2>/dev/null \
+    | grep -v -E "(^|/)($GRAPHIFY_VENDOR_DIRS)/" \
+    | grep -E -c "\.($GRAPHIFY_CODE_EXT)$"
+}
+
+# graphify_gate [dir] → "graphify? N code files ≥ T, no graph" + rc 0 when the
+# repo passes the threshold without a graph; silent rc 1 otherwise.
+graphify_gate() {
+  local root n
+  root=$(git -C "${1:-.}" rev-parse --show-toplevel 2>/dev/null) || return 1
+  [ -f "$root/graphify-out/graph.json" ] && return 1     # graph exists — nothing to propose
+  n=$(graphify_code_file_count "$root")
+  [ "$n" -ge "$GRAPHIFY_MIN_CODE_FILES" ] || return 1
+  printf 'graphify? %s code files ≥ %s, no graph\n' "$n" "$GRAPHIFY_MIN_CODE_FILES"
+}
+
+if [ "${BASH_SOURCE[0]}" = "${0}" ]; then
+  set -uo pipefail
+  graphify_gate "${1:-.}"
+fi

lib/tests/graphify-gate.test.sh

@@ -0,0 +1,60 @@
+#!/usr/bin/env bash
+# lib/tests/graphify-gate.test.sh — "propose graphify" threshold signal (BDR-097).
+set -u
+LIB="$(cd "$(dirname "$0")/../.." && pwd)/lib/graphify-gate.sh"
+WORK="$(mktemp -d)"; trap 'rm -rf "$WORK"' EXIT
+pass=0; fail=0
+check() { if [ "$2" = "$3" ]; then pass=$((pass+1)); else fail=$((fail+1));
+  printf 'FAIL %s: got[%s] want[%s]\n' "$1" "$2" "$3"; fi; }
+# gate(dir) -> the signal line, or "silent"
+gate() { bash "$LIB" "$1" 2>/dev/null || echo silent; }
+has() { case "$1" in *"$2"*) echo yes ;; *) echo no ;; esac; }
+# mkrepo <name> <n php files at root> [<n php files under vendor/>]
+mkrepo() {
+  local d="$WORK/$1" i
+  git init -q "$d"; git -C "$d" config user.email t@t; git -C "$d" config user.name t
+  git -C "$d" config core.hooksPath /dev/null
+  for i in $(seq 1 "$2"); do echo "<?php // $i" > "$d/f$i.php"; done
+  if [ "${3:-0}" -gt 0 ]; then
+    mkdir -p "$d/vendor/lib"
+    for i in $(seq 1 "$3"); do echo "<?php // v$i" > "$d/vendor/lib/v$i.php"; done
+  fi
+  git -C "$d" add -A; git -C "$d" commit -q -m init
+  echo "$d"
+}
+
+mkdir -p "$WORK/plain"
+check T1-not-a-repo "$(gate "$WORK/plain")" silent
+
+d=$(mkrepo below 199)
+check T2-199-files-silent "$(gate "$d")" silent
+
+d=$(mkrepo at 200)
+check T3-200-files-fires "$(has "$(gate "$d")" "200 code files")" yes
+check T3b-line-is-banner-sized "$([ "$(gate "$d" | wc -m)" -le 45 ] && echo yes || echo no)" yes
+mkdir -p "$d/graphify-out"; echo '{}' > "$d/graphify-out/graph.json"
+check T4-graph-exists-silent "$(gate "$d")" silent
+
+d=$(mkrepo vendored 190 60)
+check T5-vendored-not-counted "$(gate "$d")" silent
+for i in $(seq 191 200); do echo "<?php // $i" > "$d/f$i.php"; done
+git -C "$d" add -A; git -C "$d" commit -q -m more
+check T5b-own-files-reach-200 "$(has "$(gate "$d")" "200 code files")" yes
+
+d=$(mkrepo untracked 199)
+for i in $(seq 200 210); do echo "<?php // $i" > "$d/f$i.php"; done   # left untracked
+check T6-untracked-not-counted "$(gate "$d")" silent
+
+d=$(mkrepo tiny 10)
+check T7-threshold-override "$(has "$(GRAPHIFY_MIN_CODE_FILES=5 bash "$LIB" "$d" 2>/dev/null)" "≥ 5")" yes
+
+d=$(mkrepo subdir 200); mkdir -p "$d/app/sub"
+check T8-from-subdirectory "$(has "$(gate "$d/app/sub")" "200 code files")" yes
+
+d=$(mkrepo docs 10)
+for i in $(seq 1 300); do echo "# $i" > "$d/doc$i.md"; done
+git -C "$d" add -A; git -C "$d" commit -q -m docs
+check T9-non-code-not-counted "$(gate "$d")" silent
+
+echo "PASS=$pass FAIL=$fail"
+[ "$fail" -eq 0 ]