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/tool/bash_tools.rs

@@ -1,8 +1,12 @@
+//! Tool implementations for interacting with background bash jobs: `bash_output`
+//! and `bash_kill`. Both take a `job_id` produced by `bash` with `run_in_background=true`.
+
 use serde_json::{json, Value};
 use anyhow::{Result, anyhow};
 use super::Tool;
 use super::ToolCtx;
 
+/// Tool: fetch buffered output from a background bash job by `job_id`.
 pub struct BashOutput;
 
 impl Tool for BashOutput {
@@ -39,6 +43,7 @@ impl Tool for BashOutput {
     }
 }
 
+/// Tool: terminate a running background bash job by `job_id`.
 pub struct BashKill;
 
 impl Tool for BashKill {