fix(beads): prevent routes.jsonl corruption and add doctor check for rig-level routes.jsonl (#377)

* fix(beads): prevent routes.jsonl corruption from bd auto-export

When issues.jsonl doesn't exist, bd's auto-export mechanism writes
issue data to routes.jsonl, corrupting the routing configuration.

Changes:
- install.go: Create issues.jsonl before routes.jsonl at town level
- manager.go: Create issues.jsonl in rig beads; don't create routes.jsonl
  (rig-level routes.jsonl breaks bd's walk-up routing to town routes)
- Add integration tests for routes.jsonl corruption prevention

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

* fix(doctor): add check to detect and fix rig-level routes.jsonl

Add RigRoutesJSONLCheck to detect routes.jsonl files in rig .beads
directories. These files break bd's walk-up routing to town-level
routes.jsonl, causing cross-rig routing failures.

The fix unconditionally deletes rig-level routes.jsonl files since
bd will auto-export to issues.jsonl on next run.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

* test(rig): add verification that routes.jsonl does NOT exist in rig .beads

Add explicit test assertion and detailed comment explaining why rig-level
routes.jsonl files must not exist (breaks bd walk-up routing to town routes).

Also verify that issues.jsonl DOES exist (prevents bd auto-export corruption).

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

* fix(doctor): ensure town root route exists in routes.jsonl

The RoutesCheck now detects and fixes missing town root routes (hq- -> .).
This can happen when routes.jsonl is corrupted or was created without the
town route during initialization.

Changes:
- Detect missing hq- route in Run()
- Add hq- route in Fix() when missing
- Handle case where routes.jsonl is corrupted (regenerate with town route)
- Add comprehensive unit tests for route detection and fixing

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

* test(beads): fix routing integration test for routes.jsonl corruption

The TestBeadsRoutingFromTownRoot test was failing because bd's auto-export
mechanism writes issue data to routes.jsonl when issues.jsonl doesn't exist.
This corrupts the routing configuration.

Fix: Create empty issues.jsonl after bd init to prevent corruption.
This mirrors what gt install does to prevent the same bug.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

---------

Co-authored-by: julianknutsen <julianknutsen@users.noreply.github>
Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>

internal/cmd/install.go

@@ -378,6 +378,17 @@ func initTownBeads(townPath string) error {
 		fmt.Printf("   %s Could not verify repo fingerprint: %v\n", style.Dim.Render("⚠"), err)
 	}
 
+	// Ensure issues.jsonl exists BEFORE creating routes.jsonl.
+	// bd init creates beads.db but not issues.jsonl in SQLite mode.
+	// If routes.jsonl is created first, bd's auto-export will write issues to routes.jsonl,
+	// corrupting it. Creating an empty issues.jsonl prevents this.
+	issuesJSONL := filepath.Join(townPath, ".beads", "issues.jsonl")
+	if _, err := os.Stat(issuesJSONL); os.IsNotExist(err) {
+		if err := os.WriteFile(issuesJSONL, []byte{}, 0644); err != nil {
+			fmt.Printf("   %s Could not create issues.jsonl: %v\n", style.Dim.Render("⚠"), err)
+		}
+	}
+
 	// Ensure routes.jsonl has an explicit town-level mapping for hq-* beads.
 	// This keeps hq-* operations stable even when invoked from rig worktrees.
 	if err := beads.AppendRoute(townPath, beads.Route{Prefix: "hq-", Path: "."}); err != nil {