feat: add crystallizes column to sqlite storage

Adds crystallizes column for work economics (compounds vs evaporates)
per Decision 006. Includes migration 036 and updates to all INSERT/SELECT
queries in issues.go, queries.go, dependencies.go, and transaction.go.

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

internal/storage/sqlite/migrations/036_crystallizes_column.go

@@ -0,0 +1,36 @@
+package migrations
+
+import (
+	"database/sql"
+	"fmt"
+)
+
+// MigrateCrystallizesColumn adds the crystallizes column to the issues table.
+// Crystallizes tracks whether work compounds over time (true: code, features)
+// or evaporates (false: ops, support). Per Decision 006, this affects CV weighting.
+// Default is false (conservative - work evaporates unless explicitly marked).
+func MigrateCrystallizesColumn(db *sql.DB) error {
+	// Check if column already exists
+	var columnExists bool
+	err := db.QueryRow(`
+		SELECT COUNT(*) > 0
+		FROM pragma_table_info('issues')
+		WHERE name = 'crystallizes'
+	`).Scan(&columnExists)
+	if err != nil {
+		return fmt.Errorf("failed to check crystallizes column: %w", err)
+	}
+
+	if columnExists {
+		// Column already exists (e.g. created by new schema)
+		return nil
+	}
+
+	// Add the crystallizes column
+	_, err = db.Exec(`ALTER TABLE issues ADD COLUMN crystallizes INTEGER DEFAULT 0`)
+	if err != nil {
+		return fmt.Errorf("failed to add crystallizes column: %w", err)
+	}
+
+	return nil
+}