fix(db): skip SQL comment lines when parsing schema table names

parseTableNames() regex-scanned every line of schema.sql, comments
included, with 'CREATE TABLE (?:IF NOT EXISTS )?(?:\w+\.)?(\w+)'. A doc
comment containing that phrase in prose - e.g. 'declared in CREATE TABLE
above' - registered a phantom table ('above'), and startup verification
then failed with 'missing tables: above', crash-looping the app
container on every restart.

Skip lines whose trimmed form starts with '--' so comments can never
contribute table names, and add a regression test asserting every parsed
table maps back to a real CREATE TABLE statement.

internal/database/schema.go

@@ -77,6 +77,12 @@ func parseTableNames() ([]string, error) {
 	tables := make(map[string]bool)
 	for scanner.Scan() {
 		line := scanner.Text()
+		// Skip SQL comments: a doc line like "-- ... declared in CREATE
+		// TABLE above" would otherwise register a phantom table and fail
+		// startup verification.
+		if strings.HasPrefix(strings.TrimSpace(line), "--") {
+			continue
+		}
 		matches := pattern.FindStringSubmatch(line)
 		if len(matches) > 1 {
 			tableName := matches[1]