Enhance tool documentation and add new features

- Added module-level documentation for memory tools (`remember`, `recall`, `forget`) to clarify their purpose.
- Improved documentation in `recall.rs` and `remember.rs` to describe the functionality and flow of memory entry operations.
- Updated `mod.rs` to include descriptions for the tool trait and execution context.
- Enhanced `plan.rs` with detailed comments on plan-mode signaling tools.
- Documented text search tools in `search.rs` to explain their functionality.
- Improved sequential-thinking tool documentation in `seqthink.rs`.
- Added safety filter documentation in `shell_filter` for credential and git operations.
- Enhanced utility tools documentation, including `cd`, `dir_cache_update`, and `todowrite`.
- Improved rendering documentation in view modules (`chat`, `markdown`, `status`, `workflow`) to clarify rendering flows and purposes.

src/app/runtime/commands.rs

@@ -1,7 +1,18 @@
+//! Maps parsed `/` slash commands into one or more `Action` variants
+//! that `apply_action` can process.
 use crate::controller::command::Command;
 use crate::app::runtime::actions::Action;
 use crate::app::state::types::Overlay;
 
+/// Convert a parsed `Command` into the corresponding sequence of `Action`s.
+///
+/// Flow: match each `Command` variant to its handler — most produce a
+/// single `Action` (open an overlay, dispatch an OAuth flow, open the
+/// editor, etc.); some produce an `Action::SystemNote` for errors or
+/// informational responses.
+///
+/// Return: a `Vec<Action>` (always non-empty) to be applied sequentially
+/// by `apply_action`.
 pub fn apply_command(command: Command) -> Vec<Action> {
     match command {
         Command::Help => {