fix(java): resolve internal method calls using two-pass approach

When a method calls another method that is defined later in the same class, the current single-pass logic fails to find the callee method symbol and creates a stub. This commit introduces a two-pass approach within `processClass`:
1. Iterate over methods and create definitions/symbols.
2. Iterate over methods again to process method calls and resolve them against the symbols created in the first pass.

Author: li-jin-gou