Standardize API parameters to camelCase and improve LSP client reliability

- Convert tool parameters from snake_case to camelCase for consistency
- Add file existence check in LSP client before opening files
- Fix version increment timing in LSP textDocument operations
- Optimize session token tracking using onStepFinish callback
- Add debugging logs for diagnostics troubleshooting

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Co-Authored-By: opencode <noreply@opencode.ai>