fix(watcher): never re-ingest AutoTunnel's own tunnel-candidates log (#88)

Root cause was neither of the two mechanisms the issue named
(CanonicalizeLinks over-canonicalizing, or a schema/prompt bias) —
CanonicalizeLinks correctly resolved [[Mission]] because
wiki/concepts/mission.md genuinely exists; the extraction prompt has
no "mission" bias either. The real bug: watcher.processDir walks
brain/raw/ and feeds every .md/.txt/.pdf file to pipeline.Run as
source material to extract, with no exclusion for
tunnel-candidates-*.md — AutoTunnel's own fuzzy-match human-review
queue (logFuzzyCandidates writes it into that same raw/ directory).
The watcher's next poll re-ingested the raw candidate log itself, and
the LLM naturally surfaced "mission" as a wikilink because the log
literally lists `(term: "mission")` entries in its content — a
generic-word title match DetectTunnels correctly flagged as fuzzy
(not auto-tunneled) but which still leaked downstream once treated as
real source material.

api.ListPending already excludes tunnel-candidates-* when listing
raw/ for promotion; processDir gets the same exclusion.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Roq1ajWKR5f1hG5Df9wC6A

ingestion/internal/watcher/watcher.go

@@ -74,6 +74,13 @@ func processDir(ctx context.Context, cfg Config, date string) []error {
 			return nil
 		}
 
+		// AutoTunnel's own fuzzy-match human-review queue, not source
+		// material to extract (hyperguild#88) — same exclusion as
+		// api.ListPending already applies when listing raw/ for promotion.
+		if strings.HasPrefix(d.Name(), "tunnel-candidates-") {
+			return nil
+		}
+
 		// Skip files that have already been processed or permanently failed.
 		if _, err := os.Stat(path + ".processed"); err == nil {
 			return nil

ingestion/internal/watcher/watcher_test.go

@@ -229,3 +229,49 @@ func TestProcessDir_SkipsSubdirs(t *testing.T) {
 	_, err = os.Stat(failedFile)
 	assert.NoError(t, err, "failed subdir file should be untouched")
 }
+
+// TestProcessDir_SkipsTunnelCandidateFiles guards against hyperguild#88:
+// AutoTunnel's own human-review queue (brain/raw/tunnel-candidates-*.md)
+// must never be re-ingested as if it were external source material — doing
+// so fed the raw "(term: X)" log entries back through the LLM extraction
+// pipeline, which then legitimately (from its own perspective) surfaced
+// [[X]] as a wikilink for any term that happened to match a real page
+// title, however generic (e.g. "mission").
+func TestProcessDir_SkipsTunnelCandidateFiles(t *testing.T) {
+	brainDir := setupBrainDir(t)
+
+	tunnelFile := filepath.Join(brainDir, "raw", "tunnel-candidates-2026-07-19.md")
+	require.NoError(t, os.WriteFile(tunnelFile, []byte(
+		"# Tunnel candidates 2026-07-19\n\n- `wiki/homelab/decisions/foo.md` ↔ `wiki/telos/decisions/mission.md` (term: \"mission\")\n",
+	), 0o644))
+
+	var completeCalls int
+	completeFn := func(ctx context.Context, system, user string) (string, error) {
+		completeCalls++
+		raw := pipeline.RawPage{Title: "Should not be written", Type: "source", Subtype: "article", Content: "## Summary\n\nx.\n"}
+		b, _ := json.Marshal([]pipeline.RawPage{raw})
+		return string(b), nil
+	}
+
+	cfg := Config{
+		BrainDir: brainDir,
+		Interval: time.Hour, // not used; we call processDir directly
+		Pipeline: pipeline.Config{
+			Complete:  completeFn,
+			ChunkSize: 0,
+			Schema:    "# Schema\nThree page types.",
+		},
+	}
+
+	date := time.Now().UTC().Format("2006-01-02")
+	errs := processDir(context.Background(), cfg, date)
+	assert.Empty(t, errs)
+
+	assert.Zero(t, completeCalls, "tunnel-candidates file must never reach the LLM extraction pipeline")
+
+	// File must be left alone in raw/ — not moved to processed/, no marker written.
+	_, err := os.Stat(tunnelFile + ".processed")
+	assert.True(t, os.IsNotExist(err), "tunnel-candidates file should not get a .processed marker")
+	_, err = os.Stat(filepath.Join(brainDir, "raw", "processed", date, "tunnel-candidates-2026-07-19.md"))
+	assert.True(t, os.IsNotExist(err), "tunnel-candidates file should not be copied to processed/")
+}