fix(rust): replace .expect("TODO") in codegen/parser.rs (2 prod + 6 tests)

8 .expect("TODO: handle error") sites in src/codegen/parser.rs cleared.

Prod (2 sites in parse_create_table):
  Line 143: upper.find("IF NOT EXISTS") — guarded by the surrounding
    `if upper.contains("IF NOT EXISTS")` (line 141), so find returns Some.
  Line 147: upper.find("TABLE") — parse_create_table is only invoked
    when upper.starts_with("CREATE TABLE") at parse_sql_schema:100,
    so "TABLE" is always present.
  Both expect messages document the invariant — SPARK proof candidates
  per estate-wide direction.

Tests (6 sites): all parse_sql_schema(...) calls inside #[cfg(test)]
mod revert to .unwrap().

cargo test --lib: 26/26 green.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: hyperpolymath

src/codegen/parser.rs

@@ -140,11 +140,15 @@ fn parse_create_table(statement: &str) -> Result<Option<TableDef>> {
     let _before_paren = statement[..paren_start].trim();
     let name_part = if upper.contains("IF NOT EXISTS") {
         // Skip past "CREATE TABLE IF NOT EXISTS".
-        let idx = upper.find("IF NOT EXISTS").expect("TODO: handle error") + "IF NOT EXISTS".len();
+        let idx = upper.find("IF NOT EXISTS")
+            .expect("upper.contains(\"IF NOT EXISTS\") was guarded immediately above, so find() is always Some")
+            + "IF NOT EXISTS".len();
         statement[idx..paren_start].trim()
     } else {
         // Skip past "CREATE TABLE".
-        let idx = upper.find("TABLE").expect("TODO: handle error") + "TABLE".len();
+        let idx = upper.find("TABLE")
+            .expect("parse_create_table is only invoked when upper.starts_with(\"CREATE TABLE\") (see parse_sql_schema), so find(\"TABLE\") is always Some")
+            + "TABLE".len();
         statement[idx..paren_start].trim()
     };
 
@@ -329,7 +333,7 @@ mod tests {
                 created_at TIMESTAMP NOT NULL
             );
         "#;
-        let schema = parse_sql_schema(ddl).expect("TODO: handle error");
+        let schema = parse_sql_schema(ddl).unwrap();
         assert_eq!(schema.tables.len(), 1);
         assert_eq!(schema.tables[0].name, "posts");
         assert_eq!(schema.tables[0].columns.len(), 4);
@@ -358,7 +362,7 @@ mod tests {
                 title TEXT NOT NULL
             );
         "#;
-        let schema = parse_sql_schema(ddl).expect("TODO: handle error");
+        let schema = parse_sql_schema(ddl).unwrap();
         assert_eq!(schema.tables.len(), 2);
         assert_eq!(schema.tables[0].name, "users");
         assert_eq!(schema.tables[1].name, "posts");
@@ -373,7 +377,7 @@ mod tests {
                 PRIMARY KEY (post_id, tag_id)
             );
         "#;
-        let schema = parse_sql_schema(ddl).expect("TODO: handle error");
+        let schema = parse_sql_schema(ddl).unwrap();
         assert_eq!(schema.tables[0].columns.len(), 2);
         assert!(schema.tables[0].columns[0].is_primary_key);
         assert!(schema.tables[0].columns[1].is_primary_key);
@@ -382,22 +386,22 @@ mod tests {
     #[test]
     fn test_parse_if_not_exists() {
         let ddl = "CREATE TABLE IF NOT EXISTS settings (key TEXT PRIMARY KEY, value TEXT);";
-        let schema = parse_sql_schema(ddl).expect("TODO: handle error");
+        let schema = parse_sql_schema(ddl).unwrap();
         assert_eq!(schema.tables.len(), 1);
         assert_eq!(schema.tables[0].name, "settings");
     }
 
     #[test]
     fn test_parse_empty_schema() {
         let ddl = "-- just a comment\n";
-        let schema = parse_sql_schema(ddl).expect("TODO: handle error");
+        let schema = parse_sql_schema(ddl).unwrap();
         assert!(schema.tables.is_empty());
     }
 
     #[test]
     fn test_parse_varchar_with_length() {
         let ddl = "CREATE TABLE users (name VARCHAR(255) NOT NULL, email VARCHAR(320));";
-        let schema = parse_sql_schema(ddl).expect("TODO: handle error");
+        let schema = parse_sql_schema(ddl).unwrap();
         assert_eq!(schema.tables[0].columns[0].sql_type, "VARCHAR(255)");
         assert_eq!(schema.tables[0].columns[1].sql_type, "VARCHAR(320)");
     }