fix(tui): emit subagent completion before terminal update

[cyq1017]

Closes #1961

Summary

Fixes a race where <codewhale:subagent.done> completion events could be emitted after the parent turn had already proceeded to terminal update/summarization, making the assistant appear to remain active after it should have finished.

This change reorders emission so parent sub-agent completion is sent before the terminal update path executes, so completion is recorded in transcript in the expected sequence.

Changed files

• crates/tui/src/tools/subagent/mod.rs
• crates/tui/src/tools/subagent/tests.rs

Verification

• cargo fmt --all -- --check
• cargo test -p deepseek-tui run_subagent_task_emits_parent_completion_before_terminal_update
• cargo test -p deepseek-tui emit_parent_completion_fires_for_direct_child -- --nocapture
• cargo test -p deepseek-tui emit_parent_completion_skips_grandchildren -- --nocapture
• cargo test -p deepseek-tui turn_holds_open_for_running_or_completed_subagents -- --nocapture
• git diff --check

[gemini-code-assist]

Code Review

This pull request introduces support for a base_url configuration setting, allowing users to specify custom DeepSeek-compatible endpoints through the TUI and CLI. It also addresses a race condition in subagent task completion (Issue #1961) by reordering logic to emit parent completions before updating the manager's terminal state. Review feedback indicates that persist_status_items and network policy commands are currently hardcoded to use the default configuration path, suggesting they should be updated to respect custom configuration paths provided via the application state.

[gemini-code-assist]

persist_status_items is hardcoded to use the default configuration path (None). This ignores any custom configuration path provided via the --config CLI flag or the DEEPSEEK_CONFIG_PATH environment variable. This function should be updated to accept an optional path parameter, and its callers (such as in config_ui.rs) should pass app.config_path.as_deref() to ensure consistency.

[gemini-code-assist]

The network policy commands are hardcoded to use the default configuration path by passing None to config_toml_path. This causes the application to read from and write to the default ~/.deepseek/config.toml even if a custom configuration file was specified at startup. These functions should be updated to respect the active configuration path from the App state.